I've seen several grafted plants, it's very possible to make a "multi strain" mom.
If you are unable to keep multiple moms, due to limits on plants.
It's not an easy task grafting cannabis, but it's just like grafting apples or willow.
I would stay away from reveg, and only do this with healthy plants showing good growth, in a 18-20 hour light cycle!
Expect a very high fail rate, so I would attempt to make as many as possible.
Again this might be an issue, if your limited with plant numbers.
I could imagine there would be a market for these kinda moms, if someone with a nursery who don't need to worry about plant count produced them.