I'm Spanish but I've been living in the NE of Brazil for more than two decades.
I think you are a bit overthinking about long term updates. The Note 11 is a new device so you still have ahead at least 2 years of official support, with updates for Android 12 and probably 13. It's impossible to know how much custom ROM support there will be in the future for this device and you'll have plenty of time to prepare and decide which one could suit your needs best.
I saw that there are great deals for the entry model (~ R$ 1.200,00) and it's quite difficult to find a decent device for such a price. I think your only decision should be if you feel okay with the corners that were cut to offer that price (cameras, RAM management, average SoC for heavy processes ...) or not. That's all