You can use this plugin in your multilingual website setup. Please follow bellow instruction.

Setup Main page with shortcode [front-end-pm] in Dashboard > Front End PM > Settings > General > Front End PM Page. Then add following
 

Polylang

If you are Polylang user then add following code in your theme’s (child theme’s if any) functions.php
 

add_filter( 'fep_page_id_filter', function( $page_id ){
    if( $page_id && function_exists( 'pll_get_post' ) ){
        $page_id = pll_get_post( $page_id );
    }
    return $page_id;
});

WPML

If you are WPML user then add following code in your theme’s (child theme’s if any) functions.php
 

add_filter( 'fep_page_id_filter', function( $page_id ){
    if( ! $page_id || ! defined( 'ICL_SITEPRESS_VERSION' ) ){
        return $page_id;
    }
    if( version_compare( ICL_SITEPRESS_VERSION, '3.2', '>=' ) ){
        $page_id = apply_filters( 'wpml_object_id', $page_id, 'page', true  );
    } elseif( function_exists( 'icl_object_id' ) ) {
        $page_id = icl_object_id( $page_id, 'page', true );
    }
    return $page_id;
});