I was wondering can i use these in Unreal? :///3d-models/3d-model-archmodels-vol-117/699075
Looks like high poly count to me. Also check out these ://store.speedtree/product-category/ue4/
You can use nearly every mesh, but it depends on what exactly you want to do with them. 
-> for a game they look a little bit too high poly
High poly for what? What are you using them for?
I got one from there and it was too high poly. I ran decimate in blender and it looks practically the same yet its much more low poly now.
You might be able to use them as a base or reference for some lower poly trees.
was hoping for a game level cause the one we get for free in the market place from the World kite is high end looking but idk how much poly those have
Archmodels are usually catered for design/product viz, I wouldn’t personally use those- but there’s nothing stopping you from trying 
When I first looked at those I thought holy those are expensive…but I guess they really do come with a lot of varieties and all the goodies. I’m still mentally in starving college kid mode even though I’ve been out 3 years I guess lol. I might have to pick some of their stuff up at some point.
They’re not optimized for games. You’d be better off buying Speedtrees or making your own in the Speedtree Modeler.