Bad graphics when importing from Blender

I’m trying to make some trees in Blender using “Sapling tree gen”, for leaves I’m using rectangular shape, and everything is fine until I import it into UE.

This is how it looks like in Blender:

But when I import it into UE this is how it looks like:

The leaves have that green coloring around them. It is exported as .fbx format. Is there a way to fix this problem or it is a problem with “Sapling tree gen” and it is not compatible when exporting to an UE project? If that is the case what (free) alternative I can use to make realistic trees? This one is actually easy to use and you can create some nice trees with it.

Is the material set to ‘masked’?

Sorry for the late reply, I was really busy for the past week, didn’t had time to work on the game.
So, I made a few changes but now I got to a new problem, the leaves aren’t showing at all.

It looks fine here