I just started learning counterweight tricks, and I was thinking it would be interesting to try to combine offstring and counterweight together. What are your guy’s thoughts on this? Has anyone already tried it?
Yoyo Kangaroo probably has. 
This might be of interest:
Scroll on down to 9A:
From the article:
Just because it’s already been done doesn’t mean you shouldn’t continue to try it.
aww, I thought I was on to something new here :(. From that article it looks like just about everything you can do with a yoyo has been done. It will be fun to try though. But sadly I’m not very good at either counterweight or offstring, so I’ll have to work on each one first.
Here’s a video I found for it, always easier to see this sort of stuff than to try and describe it.
Josh Yee is a beast at both, he could take on the challenge if he tried 
Josh is good at everything though…
TBH just get a diabolo, its offstring with two counterweights
Double dice 4A!!!
Funny I’m surprised he didn’t make a whole thread about it.