So we could mess around and use some different Hooks for Mobile. But the simpler option would be to remove the Off Canvas Menu Label, GP will generate Aria-labels for this.
Then add this CSS to place a label on the larger screen sizes:
@media(min-width: 600px) {
.main-navigation .menu-bar-item.slideout-toggle > a:after {
content: 'Menu';
text-transform: uppercase;
}
}