RAW it's actually just reiterating that having an expertise die to a skill adds a +3 flat to passive. This was already stated in another forum thread on this same topic by Morrus himself. He did say a scaling bonus for additional expertise die probably wouldn't hurt anything either, but RAW it...
That would grant you the +3 from the expertise die & that's it. There was another thread one here where Morrus stated it's a static +3 bonus if you have any expertise die regardless of the source, the stance just grants you an expertise die to active checks (increasing the stack for other...
I hadn't fully looked into the slice of psionics book, are they compatible w/ the ParaPwr content since they were both worked on together? or are they diff attempts/looks at the psionic system independent of each other?
IIRC, there's also a section in the A5E Adventurer's Guide as well as on the A5E.Tools site and/or the LevelUp site that explains how to convert between o5e (reg 5th ed) & a5e (LevelUp) to make it easy. That being said, as Steampunkette posted above, it's relatively easy to adjust any...