Should I exchange Forza Horizon 3 for Batman Arkham Knight Premium Edition?

Value wise your forza horizon 3 is about 4 times batman ak premium edition. If you want it solely for retrade then this would make a bad trade.

no, arkham knight runs like garbage on pc. keep the forza key

As you are asking here on Steamgifts, why not create a giveaway for it?

what brightboy said. 👍

sg people being helpful as usual... next they are gonna tell you to throw away the key and buy arkham knight. 🤦‍♀️

So I get the sense you haven't done a ton of trading? A good rule of thumb used by a many traders is that trade value of a game is roughly what it would cost to obtain that game. But that is not the same thing as the game's current price on storefronts. That "price" doesn't change, whereas how cheaply the game can be obtained changes a lot. It almost always goes down over time.

Different people figure out current worth in different ways. Most traders have a rule of thumb which they apply along with some judgment. One common one is to look at sites like isthereanydeal.com and see what sale prices are standard (on the assumption that the game will soon be available for a similar price). Another is to check prices on grey market sites. (Even if you never use such sites, they can still be used as a heuristic since they reflect supply and demand.)

It's also a good idea to check if a game has been bundled. Bundled games are (or at least were) probably cheaper to obtain even than their lowest sale price. And games bundled multiple times are likely worth very little (since the versions from previous bundles are probably still up for trade, and it can be expected to be bundled again).

Forza for the win

If I was trading but not redeeming what I got, it would either have to be a gift link to ensure the key was not exposed (ie. Someone else knows it) or with someone with a high rep on Steam trades (at least 50 positive, more than 6 months on account, and no negative reps).
I've only traded for personal use and I've received used or region lock keys a few times and have gotten a new key or agreed to a different game. It wasn't people being dishonest. Sometimes they weren't sure their key was still valid or they made a mistake. Gift links and Steam gifts are just safer. Nothing can protect you from charge backs which is why rep is important too. You've got to set your own limits for risk vs reward.