Make directional light shadow only hit specific mesh renderers

I have a directional light in HDRP and a mesh renderer (1) casting a shadow on two more mesh renderers (2 and 3), but I only want mesh renderer 1 to cast a shadow on mesh renderer 2 and not on 3. Then I want to have a fourth mesh renderer cast its shadow on mesh renderer 3 but not on 2. I don't know how to acheive this in HDPR as only one directional light can cast shadows in HDPR.