Sure. I’m not sure if the images i uploaded will show in correct order, but hopefully you’ll understand.
First, if you didn’t know already, UE4 operates in cm and Blender in m. So you should set the unit scale to 0.01 and length to centimeters.(before you do anything in your scene)
So when you convert your hair particle system to a mesh, Blender gives you one object as seen in the second(?) image. You want to go into edit mode, select everything, press P and separate by Loose Parts.
Now you have a bunch of separate meshes. Select all of them and convert to curves.
That’s it, now you can select all the curves and export as alembic and UE4 should automatically detect that it is a groom if you have the plugin.
On a side note (this is not a Blender problem) I haven’t figured out how to bind the groom to the correct joints on the mannequin. Half of the groom is bound to the left foot and the other half to the right foot. Obviously that’s a problem - I want it to bound to the head.