Elementor register custom font (Font will be listed on Elementor fonts selector)

app.css

/* Enabling font which stored on fonts/ folder */
@font-face {
    font-family: 'Organetto';
    src: url('fonts/Organetto-Light.eot');
    src: local('Organetto Light'), local('Organetto-Light'),
    url('fonts/Organetto-Light.eot?#iefix') format('embedded-opentype'),
    url('fonts/Organetto-Light.woff2') format('woff2'),
    url('fonts/Organetto-Light.woff') format('woff'),
    url('fonts/Organetto-Light.ttf') format('truetype'),
    url('fonts/Organetto-Light.svg#Organetto-Light') format('svg');
    font-weight: 300;
    font-style: normal;
    font-display: swap;
}

@font-face {
    font-family: 'Organetto';
    src: url('fonts/Organetto-Regular.eot');
    src: local('Organetto Regular'), local('Organetto-Regular'),
    url('fonts/Organetto-Regular.eot?#iefix') format('embedded-opentype'),
    url('fonts/Organetto-Regular.woff2') format('woff2'),
    url('fonts/Organetto-Regular.woff') format('woff'),
    url('fonts/Organetto-Regular.ttf') format('truetype'),
    url('fonts/Organetto-Regular.svg#Organetto-Regular') format('svg');
    font-weight: normal;
    font-style: normal;
    font-display: swap;
}

@font-face {
    font-family: 'Organetto Bold SemiExp';
    src: url('fonts/Organetto-BoldSemiExp.eot');
    src: local('Organetto Bold SemiExp'), local('Organetto-BoldSemiExp'),
    url('fonts/Organetto-BoldSemiExp.eot?#iefix') format('embedded-opentype'),
    url('fonts/Organetto-BoldSemiExp.woff2') format('woff2'),
    url('fonts/Organetto-BoldSemiExp.woff') format('woff'),
    url('fonts/Organetto-BoldSemiExp.ttf') format('truetype'),
    url('fonts/Organetto-BoldSemiExp.svg#Organetto-BoldSemiExp') format('svg');
    font-weight: bold;
    font-style: normal;
    font-display: swap;
}

@font-face {
    font-family: 'Organetto';
    src: url('fonts/Organetto-Bold.eot');
    src: local('Organetto Bold'), local('Organetto-Bold'),
    url('fonts/Organetto-Bold.eot?#iefix') format('embedded-opentype'),
    url('fonts/Organetto-Bold.woff2') format('woff2'),
    url('fonts/Organetto-Bold.woff') format('woff'),
    url('fonts/Organetto-Bold.ttf') format('truetype'),
    url('fonts/Organetto-Bold.svg#Organetto-Bold') format('svg');
    font-weight: bold;
    font-style: normal;
    font-display: swap;
}

functions.php

<?php

/**
 * Elementor register custom font
 * Responsible to modify the fonts list in the font control.
 */
function modify_controls($controls_registry) {
    // First we get the fonts setting of the font control
    $fonts = $controls_registry->get_control( 'font' )->get_settings('options');
    // Then we append the custom font family in the list of the fonts we retrieved in the previous step
    $new_fonts = array_merge([
        'Organetto' => 'system',
        'Organetto Bold SemiExp' => 'system',
    ], $fonts);
    // Then we set a new list of fonts as the fonts setting of the font control
    $controls_registry->get_control( 'font' )->set_settings( 'options', $new_fonts );
}
add_action( 'elementor/controls/controls_registered', 'modify_controls', 10, 1 );