it is not only the double button – you can insert on caption for example this:
( just style it on the page bottom – copy that enfold button shortcode and insert it on captions field )

[av_button label='Click me' icon_select='yes-right-icon' icon='ue82b' font='entypo-fontello' icon_hover='aviaTBicon_hover' title_attr='' button_type='' link='manually,#' link_dynamic='' link_target='' download_file='https://' attachment='' attachment_size='' downloaded_file_name='' size='large' position='center' label_display='' size-text='' av-desktop-font-size-text='' av-medium-font-size-text='' av-small-font-size-text='' av-mini-font-size-text='' margin='' margin_sync='true' padding='' padding_sync='true' av-desktop-margin='' av-desktop-margin_sync='true' av-desktop-padding='' av-desktop-padding_sync='true' av-medium-margin='' av-medium-margin_sync='true' av-medium-padding='' av-medium-padding_sync='true' av-small-margin='' av-small-margin_sync='true' av-small-padding='' av-small-padding_sync='true' av-mini-margin='' av-mini-margin_sync='true' av-mini-padding='' av-mini-padding_sync='true' color_options='' color='theme-color' custom_bg='#444444' custom_font='#ffffff' btn_color_bg='theme-color' btn_custom_grad_direction='vertical' btn_custom_grad_1='#000000' btn_custom_grad_2='#ffffff' btn_custom_grad_3='' btn_custom_grad_opacity='0.7' btn_custom_bg='#444444' btn_color_bg_hover='theme-color-highlight' btn_custom_bg_hover='#444444' btn_color_font='theme-color' btn_custom_font='#ffffff' btn_color_font_hover='white' btn_custom_font_hover='#ffffff' border='' border_width='' border_width_sync='true' border_color='' border_radius='' border_radius_sync='true' box_shadow='' box_shadow_style='0px,0px,0px,0px' box_shadow_color='' animation='' animation_duration='' animation_custom_bg_color='' animation_z_index_curtain='100' hover_opacity='' sonar_effect_effect='' sonar_effect_color='' sonar_effect_duration='1' sonar_effect_scale='' sonar_effect_opac='0.5' css_position='' css_position_location=',,,' css_position_z_index='' av-desktop-css_position='' av-desktop-css_position_location=',,,' av-desktop-css_position_z_index='' av-medium-css_position='' av-medium-css_position_location=',,,' av-medium-css_position_z_index='' av-small-css_position='' av-small-css_position_location=',,,' av-small-css_position_z_index='' av-mini-css_position='' av-mini-css_position_location=',,,' av-mini-css_position_z_index='' id='' custom_class='conversion' template_class='' element_template='' one_element_template='' av_uid='av-lu0tlroy' sc_version='1.0' admin_preview_bg='']

As you can see on that second image – not all of the code is needed. This is the main you need for a button – change size and position to your need and maybe remove icon_hover attribute. maybe set a custom class or ID. How to get the icon codes ? … ask.

[av_button label='your button label' icon_select='yes' icon='ue859' font='entypo-fontello' icon_hover='aviaTBicon_hover' link='manually,#' link_target='' size='medium' position='center' label_display='' title_attr='' color='light' custom_bg='' custom_font='' id='abc' custom_class='def']

it seems that on some classical posts ( not generated by ALB ) there is an image on the bottom that represents the featured image of that post – remove it by:
( see for example: https://enfold.webers-webdesign.de/standard-post/ )

#footer-page .entry-content-header {
  display: none;
}

the icon you like to insert – is it a colored icon or do you like to use the white globe icon with that green background?

if you like to use it as monochrome icon – i would upload that monochrome globe as svg to fontello and create your custom icon font set.
Then you can use it like all the other entypo-fontello icons.

if you like to use that bicolor globe icon – you can set those icons to display none and insert via pseudo container your colored icon:

#top #main ul.avia-icon-list.av-iconlist-small  li:before {
    content: "" !important;
    width: 40px;
    height: 40px;
    float: left;
    margin-left: -10px;
    margin-right: 10px;
    background-color: transparent;  /**** with background - replace  ***/
    background-image: url(/wp-content/uploads/globe-color.png);
    background-size: 30px 30px;
    background-repeat: no-repeat;
    background-position: center;
    border-radius: 100%;
    top: -3px;
    position: relative;
}

#top .avia-icon-list-container .iconlist_icon {
  display: none 
}

But: to better select your small icon list – it would certainly be advisable to use a custom class.