You can't change your region, but you can create a new profile. The problem here is that when making payments your region is locked into the billing address, so your credit card won't work.
Despite having 2 profiles, you can still play games that you've purchased on your SA account.
I play with my SA account, but purchase games and DLC via my norwegian account. If it gets downloaded on the same console, it's accessible to anyone with an account on that console.
Same works for the gf who made a norwegian account so she doesn't destroy my save files while playing games I bought on my SA account.