I'll show a picture.
See, in Zdoom the weapon flips normally.

But in GZdoom it shows the same graphic.

I kind of do this to save space and stuff. I also do this on floor sprite graphics like explosions and fire to break up the monotony of seeing the sprites the same way all the time.
So does anyone get what I'm trying to say here?
If the person who fixes this stuff in Gzdoom wants a copy of this wad I can give it to him.