I am looking how to set Revit Link Path Type to Relative from Absolute.
The Reference Type is a Revit Link Type parameter but the Path Type no idea.

I am looking how to set Revit Link Path Type to Relative from Absolute.
The Reference Type is a Revit Link Type parameter but the Path Type no idea.

Looks to be a Revit Link Type property.
Parameter Name: Path Type, does not work

It is a Property, not a parameter. You will need to get the LinkType and then set the Property
RVTLinkeType.PathType = PathType.Absolute
I assume there will be some Python involved unless there is a SetProperty node out there.
PathType Enumeration (revitapidocs.com)