The fact that this is my 3rd thread about this subject ..

Anywho, I wanna remove a lifetime reward. I can't do it through master controller because I just can't find traits and I can't really delete it through testingcheatsenabled true.
I've tried googling it but can't really find something useful. Any ideas?

You can do it with MasterController.

MasterController >> Advanced >> Traits >> Drop Rewards

Click this link then scroll down and find the "Cheats" one that matches your patch level . It's required for the "Traits" menu to show up.

Look, in your first thread I linked to the MasterController manual; there it says what Kawab already wrote and that you need the MasterController Cheats module in addition. I'm sure you'll figure it out, smart as you are, without creating a whole new website for this.

I think it was a bit hard to figure that out when all you gave me was a long list of what mastercontroller did, and that list is long

Yes, and I gave you the correct name of the interaction, so hitting ctrl-f in your browser and search for it there instead of google would have been so much faster
But I guess you managed nevertheless, didn't you?