[Elementor] Adding fonts to typography options

functions.php

<?php

/**
* Adding fonts to Elementor typography options
*/
function ching_add_fonts_elementor( $controls_registry ) {
    // retrieve fonts list from Elementor
    $fonts = $controls_registry->get_control( 'font' )->get_settings( 'options' );
    // add your new custom font
    $new_fonts = array_merge( [ 'Your Custom Font Family Name' => 'system' ], $fonts );
    // return the new list of fonts
    $controls_registry->get_control( 'font' )->set_settings( 'options', $new_fonts );
}
add_action( 'elementor/controls/controls_registered', 'ching_add_fonts_elementor', 10, 1 );