Swap header logo based on Polylang Locale

I don't know how to filter the logo source, but you could remove the logo, localise it, then stick it back in...

add_action( 'wp', 'remove_brand_logo' );

function remove_brand_logo() {

    beans_remove_markup('beans_logo_image');

}

add_action( 'beans_site_title_link_append_markup', 'localise_and_add_logo' );

function localise_and_add_logo() {

    $lang = get_bloginfo("language");

    switch ($lang) {
        case 'en-CA':
            $logo = "http://mydomain.com/wp-content/uploads/2017/09/logo.png";
            break;
        case 'fr-CA':
            $logo = "http://mydomain.com/wp-content/uploads/2017/09/logo_fr.png";
            break;
    }

    ?>

    <img class="tm-logo" src="<?php echo $logo; ?>" alt="" data-markup-id="beans_logo_image">

    <?php

}