Rikards way is the best – give a custom-class to your slider and let it be part of the selector to the heading you like to change
the custom-class will be on the slider itself (

.custom-class .avia-caption-title {
    color: red;
}

(maybe an !important is neccessary)

btw: there is no class : avia-caption on the tree there is : slideshow_caption

Edit: sorry on easy slider there is avia-caption class !

___________
next if you like to influence it in dependency to the slide you had to insert slide class ( slide-1, slide-2 etc.)

.custom-class .slide-1 .avia-caption-title {
    color: red;
}

_____________

BUT: there is the way in the slider ALB Element itself to change the font-color:
On Styling Tab you got:

Edit: sorry on easy slider there is this option missing – only for full-screen or full-width slider

_________
offtopic:
well this is not the right way.
There are attribute selctors that could be used. – You find a good list f.e. here https://developer.mozilla.org/en-US/docs/Web/CSS/Attribute_selectors
but even those selectors are outside the curly brackets f.e.:

.anotherelement img[src*="yourpic"] {
your css code here …
}

that littel asterisk means : contains at least one occurrence of value (yourpic) within the string
the list is big see link above ( *, $, ^, ~, |, etc. pp )

hm – the button color of the non hovered state can you try the li itself – not the anchor!

.av-share-box ul li.av-share-link {
    background-color: #eee;
}

in your case this would be:
( do not forget to change back the Element Visibility )

@media only screen and (max-width: 767px) {
	.responsive .avia_responsive_table .avia-data-table tr.avia-heading-row th {
		display:none
	}

	.avia-table-6 tr:nth-of-type(2) td:nth-of-type(1):before { content: 'DI-bokser:'; font-size: 14px; font-weight: 700; text-transform: capitalize; } 
	.avia-table-6 tr:nth-of-type(2) td:nth-of-type(2):before { content: 'Shure:'; font-size: 14px; font-weight: 700; text-transform: capitalize; } 
	.avia-table-6 tr:nth-of-type(2) td:nth-of-type(3):before { content: 'DPA:'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(2) td:nth-of-type(4):before { content: 'Sennheiser'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(2) td:nth-of-type(5):before { content: 'AKG:'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 

	.avia-table-6 tr:nth-of-type(4) td:nth-of-type(1):before { content: 'Audio Technica:'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(4) td:nth-of-type(2):before { content: 'Neuman:'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(4) td:nth-of-type(3):before { content: 'Beyer Dynamic:'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(4) td:nth-of-type(4):before { content: 'Diverse'; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
	.avia-table-6 tr:nth-of-type(4) td:nth-of-type(5):before { content: ''; font-size: 14px; font-weight: 700; text-transform: capitalize;} 
}

well the first thing they did not think of – is that there could be more heading rows than one!

so this rule affects only the first heading-row:

@media only screen and (max-width:767px) {
	.responsive .avia_responsive_table .avia-data-table tr:first-child th {
	  display:none
	}
}

put in your quick css:

@media only screen and (max-width:767px) {
	.responsive .avia_responsive_table .avia-data-table tr.avia-heading-row th {
	  display:none
	}
}

the next thing is the wrong heading ( maybe one update will fix that – it will always take only the first heading-row )
because heading in responsive case comes via pseudo container – we had now to find the rules for that …
just looking to find a solution

Edit: hm – guess there is no simple solution for tables with multiple heading-rows.
Guess you had to setup two tables for that – one for wider screens and the other for your mobile version.
There is an option on the alb element on Advanced – Element Visibility
The first one got 3 columns and 2 heading rows –
The mobile one got 6 columns and 1 heading row

see here: https://webers-testseite.de/tables/

the whole Enfold Options are language specific on WPML. You can see that in the upper left corner – there are flags indicating the independent use of Enfold Options for languages.
So even the Quick Css fields are different when you switch languages in Enfold Options. Some say this is a bug – I think it’s an added benefit.
I always style all my settings for my main language first – even with all the quick css I need.
Then I sync the settings by exporting the theme settings file – switch to the other language in the backend – and load the theme settings file into the new language. – This for each language you have.
After that, if you want to style the language differently you can start customizing.

so I suspect that in your main language you have set the Footer settings to German and left them at a different setting in the other language.

So if there are any quick css entries afterwards, you have to remember to add them for the other languages as well. In this case I do not go over the theme settings files but transfer them manually.

well the a[href*=".webp"] is allready included to 4.8.0-dev-6 but the a[href*=".webp?"] is missing – so wait til next update and change it on your parent theme file : avia-snippet-lightbox.js yourself without the child-theme construct from above and the next update will bring it back.

Well a lot of the other mates do not.
And with one post so far, I just wanted to make sure it wasn’t due to such a trivial error.

3a) if you like to have your own “backlink” you can insert this to your child-theme functions.php:

/**  new backlink in copyright insertion*/
function new_nolink(){
$kriesi_at_backlink = "<a href='https://your-wanted-backlink-path'>Your Backlink Text</a>";
return $kriesi_at_backlink;
}
add_filter("kriesi_backlink","new_nolink");

alternative the newest way :

add_filter( 'kriesi_backlink', 'my_own_backlink', 10, 1);
function my_own_backlink($link){ 
  $theme_string = 'Custom Backlink Text'; 
  $backlink_url = 'Backlink URL';
  $no = "rel='nofollow'";
  $link = " - <a {$no} href='{$backlink_url}' target='_blank'>{$theme_string}</a>";
  return $link;
}

which font do you want to include?
do you have all font-weights you need in that zip file you upload? / or in the folder you upload?

a good starting (not only for google fonts – but for comparison) – this page could show you how it works to load fonts locally:
https://google-webfonts-helper.herokuapp.com/fonts

If you choose in the list on the left side one font – you an see on the right side the options you have.
On 2. Style select you can make your choice what font-style you like to include – if you want to do it exactly, you should select the italic fonts as well. Often it is enough to leave this display to the browser. Because every font style that should be loaded costs performance.
On 3. you can decide if you like to support even older browsers – or to load only modern browser support ( only woff and woff2)

first it is set to 100% in base.css ( inside the css folder )
a little down that definition it is set to:

/*default*/
h1, h2, h3, h4, h5, h6 {
/*	font-family: "Georgia", "Times New Roman", Helvetica, Arial, sans-serif; */
	font-weight: 600; }
#top h1 a, #top h2 a, #top h3 a, #top h4 a, #top h5 a, #top h6 a { font-weight: inherit; text-decoration: none; color: inherit; }
#top h1 strong, #top h2 strong, #top h3 strong, #top h4 strong, #top h5 strong, #top h6 strong { color: inherit; }
h1 { font-size: 34px; line-height: 1.1em; margin-bottom: 14px;}
h2 { font-size: 28px; line-height: 1.1em; margin-bottom: 10px; }
h3 { font-size: 20px; line-height: 1.1em; margin-bottom: 8px; }  /*28*/
h4 { font-size: 18px; line-height: 1.1em; margin-bottom: 4px; }  /*21*/
h5 { font-size: 16px; line-height: 1.1em; }  /*17*/
h6 { font-size: 14px; line-height: 1.1em; }

the option in the Enfold settings dialog “Default content font size” sets the size for the body. Many font size definitions go back to this value

sorry no private content for me – i’m participant as you!

but all pages except the front page :

function add_class_to_images(){
if(is_page() && !is_front_page()){
?>
<script>
	(function($) {		
		$('img').addClass('zoooom');
	})(jQuery);
</script>
<?php
}
} 
add_action('wp_footer', 'add_class_to_images');

the Exclamation mark indicates a not logic so it is all pages but not front page
PS: is_home() might work here too – but there is a little difference inbetween is_front_page() and is_home()

Well you can use every conditional tag wordpress offers: https://codex.wordpress.org/Conditional_Tags
a douple pipe is a logic or and a double && is a logic and
so you can start with – the if clause wraps the script that should be used.
e.g.:

function add_class_to_images(){
	if(is_page() || is_singular('post') || is_singular('portfolio')){
		?>
			<script>
				(function($) {		
					$('img').addClass('zoooom');
				})(jQuery);
			</script>
		<?php
	}   // this closes the if statement
}   // this closes the function itself
add_action('wp_footer', 'add_class_to_images');

//more specific selections can be made within the brackets. (e.g. - which pages should be affected via an array). 
// IDs without quotes and page names like privacy , portfolio etc. with quotes
if(is_page(array( 1396, 1617, 'privacy'))){ …

it might be better to see your pages it concerns to give exact help on that.