Iam using UE 4.27 and have found that tessellation isnt supported in directx 12,since iam in UE 4 and not using directx 11(ie has tessellation) my options seem to be write my own displacement shaders in UE 4.
@dctrdrjtfs did you ever find an answer? We seem to have the issue where we use D3D12 but lose Tessellation on Xbox One and Series X/S, but its fine on PC.