"Easy" depends on your definitions!
There's a lovely walking path along the canal that starts right near the SSR boat dock and takes you over to South Point at OKW...total distance is, as I recall, just about a mile (depending on where in SSR you start from and where in OKW you wind up)...I love this path and walk between SSR and OKW frequently...it's a 15 to 20 minute stroll for me...
There is also boat service between SSR and DTD, and between DTD and OKW...last time I used it, the route included stops at both SSR and OKW, but I believe they've changed the routes so you may have to change boats at DTD now...not sure about that...but the boat rides are relaxing and fun all by themselves (altho not particularly "quick")...
And there are the buses...you can use the internal bus routes at both OKW and SSR to get you to the start/end of the walking path; or you can take a "regular" bus to Downtown Disney and then transfer to "the other" resort...
So, I think it's easy...but my definition of easy may be broader than some others!
Good luck w/your planning...