Flex column animation at the end of a page not triggering

you can use the implemented waypoint script but have your own settings with child-theme functions.php.

for some enfold animations it is only necessary to have fired it once the point of triggering is passed. But sometimes it is nice to include if scroll-direction is important:
f.e. if you like to move a container from off-screen to the center – and on scrolling up it will go off-screen again

for that i use to toggle a class to which i can give the animation rules. The element to observe gets a custom class ( f.e. inview )

function scroll_up_down_change() {
?>
<script>
    (function($) {
	var element_to_animate = $('.inview');
	element_to_animate1.waypoint(function(direction) {
		if (direction === 'down') {
			$(this.element).addClass('animate-now');
		}
	 },{offset: '90%'}
	);
	element_to_animate1.waypoint(function(direction) {
		if (direction === 'up') {
			$(this.element).toggleClass('animate-now');
		}
	 },{offset: '90%'}
	);			  
})(jQuery);
</script>
<?php
}
add_action('wp_footer', 'scroll_up_down_change', 9999);

then you can play with offset too.
By the way i believe the 100% offset is if it comes on the bottom into view – so maybe the 90% will do the trick on the change above

See here the last button on that page uses 90% : https://webers-testseite.de/buttons/

and an enfold animation – but you can have your own keyframes aswell – just define it for the toggled class.
Or: See here how it can be used to change header_bg background-color on color-section dependencies.: https://kriesi.at/support/topic/menu-bar-with-dynamically-changing-colors-referencing-the-background/#post-1161520