When I try boot outriders from the wemod app, I get an error saying check installation or anti virus??
I haven’t got any anti virus on my pc
Welcome to the community. 
Yes, you have. All Windows PCs come with Windows Defender on them, which is an antivirus that cannot be removed because it is embedded into the operating system.
See here for troubleshooting: I can’t Install WeMod / “There was a error installing the application” - WeMod App / Support.
I have permanently disabled windows defender through a app
Make sure you have read and correctly followed the launch instructions for the trainer by clicking the Info button in there.
And make sure you are using the correct trainer for the store that you got the game from. Note that WeMod does not provide trainers for cracked versions, if that’s what you have. 