Oh don't feel bad, I'm always down to help!
I never tried Unreal before but I just downloaded it to test a bit, my low end computer barely runs it haha
So first you need to import the fbx and it's respective png texture like normal, first double click the png and change the texture filter to nearest:
Then double click on the material and change the Blend Mode to "Masked":
After that you drag the png image to the material and arrange it like this:
And it works!
Looks weird with this shading but I'm sure you know how to make it better, make sure to disable mipmaps and stuff like that.
Anyway I hope it helps, feel free to ask if you have more questions!