Hi, recently I discover TreeIt! (and awesome free software for genererate trees, and come with templates)
Tweaking the templates I did more than 100 trees classified in 16 different spices (thanks to the templates) And I put it all together in a UE4 project so is easy to migrate to others.
Most of the trees have 4 Lods, the last is a billboard
Inside the project folder you fill find a folder called “project files” where you will find the obj and textures in case you want to import in other app, oh! and also a TreeiT! templates in case you want to open the trees in TreeiT and change something
I hope you find it useful!
Free Download: Trees Library
Some pictures more here: https://www.artstation.com/artwork/By4R8