Cannot use Halo reach or change language on pc

Hi, I come from Spain and I have two problems with the game. Im under game pass subscription and installed MCC and halo reach. My store settings are in spanish, my pc region is set to Spain and my windows 10 language setted to English (United states). The two problems are:

  1. When I try to play halo reach campain or multiplayer I see this message: “Content not installed or still downloading…” (in spanish of course) No matter what I try, reinstalling, changing windows language, store language nothing seems to work.

  2. I would like to change in game voice and texts language from spanish to english. I love to hear the “king of the hill!!” voices from my old days in xbox.

I have found two posts exactly resolving this two issues but the solution are for steam so my question is how do I solve this on xbox (beta) app on windows 10? In the two posts talks about downloading MCC Reach extended language pack. Where in the hell can I download this on windows store or xbox app?

This are the two posts for steam:

Thank you!

In case there is someone with this problem I have managed to solve it thanks to this post:

Going to settings accesibility there is an option to change language, there you can set your language and the missing content message dissapears and you can start playing. Thanks 343 for this language selection feature. There are a lot of people like me that prefer the game in VO. The coallition should do the same with gears5 to prevent users to edit manually config files to set EN as the main language.