Doing a line trace on a landscape does not return the correct physical material unless "Generate Overlap Events" was enabled after changing the physical material. If the physical material on the landscape is changed, then "Generate Overlap Events" must be unchecked and checked again to produce the correct result.
Found in CL# 4.19 4033788, 4.20 CL# 4233996, 4.21 CL# 4275031
Maybe be similar to UE-60798
The line trace will return FirstPM rather than SecondPM.
The line trace should return the proper physical material that is set
There's no existing public thread on this issue, so head over toAnswerHub just mention UE-62830 in the post.