Moved to Brazil from the UK (Power problems)

I did a little bit of research for you. You wouldn't need to spend a bunch of money buying a whole new power brick, you'd simply just need the power/plug adapter... which I'm sure they sell somewhere there. Brazil uses a Type N outlet/plug and those apparently
also work with Type C plug/outlets.

This website kind of gives you the rundown about power outlets/plugs worldwide and I think you may find it to be very useful. https://www.power-plugs-sockets.com/brazil/

My understanding of it would be that you can buy an official power brick from brazil and it should work. However, talk to someone in the store before trying it out.

Hello Ultima, on Brasil Xbox One Power Brick are bivolt, try to buy a new power brick to prevent problems.

Search the internet for an Xbox branded power brick.

[quote user="jamescisv"]With the above arrangement, would there be a problem playing a game bought in the US, or Brazil with a UK based account? [/quote]

Disc based games will not have any problem, but downloaded games (and downloaded content) will. Anything bought on a UK based account must be bought from the UK marketplace, using UK payment options. Your physical location doesn't
matter. This can easily be done by changing your console location to UK in the system settings, and by using pre-paid UK Microsoft credit (which many places sell online).

[quote user="jamescisv"]Would there be a problem downloading additional content in Brazil, for a game I'd purchased in the UK (or US)?[/quote]

There shouldn't be any problem there

[quote user="jamescisv"]Indeed, would I be prevented from downloading additional content etc, if my account's UK registered, but the game's bought in Brazil (or the US)?[/quote]

It should be noted that anything downloaded on the Brazilian marketplace can only be bought on a Brazilian account. Same goes for stuff on the US marketplace. If you buy a disc game in Brazil, then add UK DLC, you won't have
a problem. If you download a game on your UK account (from the UK marketplace), then buy DLC using a second Brazilian account (from the Brazilian marketplace) it should theoretically work (I'm not 100% sure), but you will need both accounts signed in while
playing that game.

[quote user="jamescisv"]Would I still be able to download full games, Games with Gold, etc, from the UK store, even though I was based in Brazil?[/quote]

If the location in the system settings of your console is set to UK, then yes.

[quote user="jamescisv"]And finally, is it even possible to have a UK based account - particularly if I
buy the Xbox One from the US, and then set it up in Brazil?[/quote]

Yes.

A couple of options that may make things easier for you.

1) If possible, you could change your account region from UK to Brazil. Where the console is bought from doesn't matter.

2) If you can't change the region of the account,or you don't want to, you can make a second silver Brazilian account which you can use to buy stuff from your local marketplace. As long as it's a silver account, you won't be
able to get stuff like "Games with Gold", and "Deals with Gold" though. You will also need to be signed in on that account while playing that game on you main account.