How can I override the sitemap route?

[mauriciodinamarca]

Hello
I was looking at the Statamic's Discord (link here) and also here (issue 148 and I can't find a way to override it.
We have a lot of entries (+107.000) using eloquent driver in Database but when visiting the url it throws a FatalException (we think that it should be the amount of data to put into an collection / array):

Symfony\Component\ErrorHandler\Error\FatalError
Allowed memory size of 536870912 bytes exhausted (tried to allocate 237568 bytes)

We tried to add something like in the routes/web.php file but without success:
Route::get('/sitemap.xml', [\App\Http\Controllers\SitemapController::class, 'index']);

Thanks in advance