How to pass action to Laravel 8 routes?

I was using following Route declaration to pass language action to the routes.

Route::get('/de', ['uses' => 'PageController@showHomepage', 'language' => 'de']);

And in controller, I was able to get this value like this:

$action = $request->route()->getAction();
// $action['language'] gives the given value here..

But with callable syntax, I couldn’t find how can I do the same thing. When using the following type of route definition:

Route::get('/', [PageController::class, 'showHomepage']);

How can I pass the language to new declaration? Is that a way to pass arguments to callable in Route::get() ?

Something like this

Route::get('/', ([PageController::class, 'showHomepage'],'languagecode_parameter_here'));

Thank you very much.

PS: If you are asking why do I need such custom parameter, here is more details about the need: https://github.com/laravel/framework/discussions/44839