Unfortunately not at this time in any size that will do any good. I have brought in terrains from other engine exports, but there are issues in placing game object and shadows. AI seems to follow fine on this.
You can get height maps and bring them in threw a third party program mage by one of our users Board Of the Ring.
https://forum.game-guru.com/thread/221333RIP
Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz, 2400 Mhz, 4 Core(s), 4 Logical Processor(s), 8gb RAM, Nvidia gtx660, Windows 7 Pro 64bit, Screen resolution 1680 x 1050.
New:
Intel(R) Core(TM) i5-8400 CPU @ 2.81GHz, 12GB RAM, Nvidia gtx1050ti 4gb, Windows 10 Home 64bit, Screen resolution 1920 x 1080. System Passmark 3774