$locations = get_the_terms( get_post(), 'locations' );

$locations_grouped = [];

foreach( $locations as $location ) {

    $location_type = get_term_meta( $location->term_id, 'location-type', true );

    if ( ! $location_type) {
        $type = 'other';
    }

    if ( ! array_key_exists( $location_type, $locations_grouped ) ) {
        $locations_grouped[$location_type] = [];
    }

    $locations_grouped[$location_type] = $location;

}