Can I influence my Steam region?

Solution 1:

Your intent may be different, but I'll give you the same answer as on the suspected duplicate:

Ask your friend to buy the game for you and give it to you as a gift. (If he doesn't have an account yet, he should register with his actual location and, most importantly, his credit card/Paypal account.)

That has always worked for me so far, although I haven't tried with Unreal in particular.

Solution 2:

Valve can (and has) locked out games attached to peoples Steam accounts that are from a different region than the one they live in.

This was a big deal with the Orange Box first launched.