I can find someone here:

Middleman for Game keys trade for cash

 

Hey @rwmwovwopw

I'm sure there's a middleman that would help with this - you can find the middleman forum here:
MiddleMan Forums

Be sure to do your research and ensure you're speaking with the right person if you use Discord.
I'd recommend reading the following threads:

How to Identify & Avoid Being Scammed on Discord [Guide]
A warning to all Discord traders

 

how can I trust any middleman here? I found out only about vouchers. but that's not a guarantee. it can be fake or some else. and there is no person who left vouch after was scammed. suspicious right? so it's always risk? @Sound thx

 

Hey @rwmwovwopw
There's never a guarantee when dealing with things online.
You need to do some research. Choosing someone with a very strong reputation, and being vigilant that you're speaking to the right person and not an impostor, will mean you're extremely likely to be safe. That said, there's always a risk with virtual transactions, there's no way to ever be 100% safe.

Hope this helps!