How do you switch accounts?

Hello

My wife and I would like to play this game. I installed this game under my account on our computer?. But is there anyway for her to register an account and play as well in the game client?

Or do you have to log into the microsoft store as a separate account and install 2 copies of the same game. (When my wife logged into the microsoft store, it asks for her to install the game again, even though it's already installed under my profile)

Is there anyway to log into your game account in the game client?

You should be able to use the Xbox Console Companion App. You should just need to login with the account you want to play on and load the game from there.