> I had a Pixel 6a with Graphene OS for a year before the phone started to glitch and eventually die. It ran pretty hot; sometimes it was hard to even hold the phone in my hands without burning myself.

This sounds like your phone may have been one of the Pixel 6a models with a defective battery[1]. It was a major problem for which Google pushed out an update that nerfed the battery life. There is a tool online where you can check if your particular 6a was one with a battery from the bad production batch[2].

But that unfortunately doesn't help if you are in Brazil where, as you say, Pixels aren't officially sold and import/export controls tend to make tech warranties useless in practice.

[1] https://www.lifewire.com/pixel-6a-battery-overheating-warnin...

[2] https://support.google.com/pixelphone/answer/16340779?hl=en