I'd be willing to trade it for Firewatch. P.S. Sorry for late response, dropped a soda can and it exploded in my room.
Ouch, that's not fun.
But no, I definitely can't give Firewatch for it. For reference, you're willing to accept 50 cards, but Firewatch is worth in the ballpark of 400-500 cards or more depending on when and who.
I'm not an experienced trader, I just pulled the 50 cards out of my ass. By that logic MGS:V would be worth 800-1000 cards based on price. (Edit) Minus the region locked negative.
Either I missed it - which I don't think I did - or you just added the region locked part. Can't use this game.
I swear I just typed a whole thing to help you out as a new trader trying to understand values, but the short version is don't pay any attention to places like Steam. Steam prices mean nothing for actual market value. Check g2a and spend some time on this forum and looking at isthereanydeal and you'll eventually get the picture.
Metal Gear Solid V
Game of equal value / 100 trading cards.