[Mistri]

I do the same thing as OP - I have multiple separate containers, each has its own set of cookies, and its own Google account that it is logged into. I just change my window when I want to use a different account.

From what I understand, you're asking how you can just "temporarily" log into an account — can't you just add that account as a new user on Chrome?

If not, you can always open an incognito window or a guest window, do your business, and close it. I do that often when I'm logging into an account that I don't want to persist.