I live in Brazil, however I want to switch both my Microsoft Account's and my computers' region to US and all languages to United States english in order to have access to features only available there for now, such as the Paint Cocreator. I did change all settings on my MS account and even fresh installed Windows using the EN-US ISO. However, as soon as I login into Windows with the MS account, the PC's regional settings as well as the regional settings on the Microsoft account page itself get bypassed and automatically reversed to Portuguese-Brazil. After a while most Windows apps change their language to PT-BR and I can't seem to be able to reverse this. Noticed Windows becomes borked, UI is unresponsive, apps such as the task manager take unusually long to open and even system updates bug out when I try to install them. I can't even revert things back to PT-BR as I now get apps and UI elements with mixed languages all over the system. Edit: Solution was easy enough. Just needed to set "Apps and Sites" language to US English.
MS generally ignores local settings, period, because they think that they know better, what the user wants. I tried Bing for 3 months and local settings were ignored, I switched to Brave, not a single local result.