Welcome to the community @Strongylos. 
This is known as a false positive. You will experience this from time to time with trainers, no matter where on the internet you get them from. It is triggered purely as a precaution because of the way trainers work. They are completely harmless.
The fix is to add WeMod as an exception.
Please use the search feature in the community before posting. You would have very quickly found this thread, which explains why it happens and how to resolve it: Windows Defender marked WeMod as a Trojan.