Strange white line at the bottom of every imported .png/.tga

I am currently trying to create a 2d platformer game and downloaded a tileset to use it in UE4. But when I import the perfectly fine texture, UE4 creates a strange white/light green line at the bottom of the texture, making it look very strange in a tile map. I tried it with the texture in .png format (thats how I downloaded them) and in .tga format. It happens in both cases.

How it looks like in editor:

Thanks in advance :slight_smile: