Look at texture, wtf?
What program are you using to create your splat maps? From the filename it looks like World Machine - if it is, you may have to play with the Edge Blending - also make sure that the option “Calculate edge tiles on partial tilesets” is set. Check out http://forum.world-machine.com/index.php?topic=2400.0
Have you zoomed in from the World Composition window in UE and made sure it is aligned perfectly?
Yes, aligned good
I’m afraid I’m out of ideas, my guess is the stretched texture (1009) is antialiasing the edges - perhaps you could make it 1010 so it overlaps?
No, not 1010, i create one splatmap for all world, and problem fixed, thx for all )