In this AU, instead of meeting Sage, Vert meets Krytus.
Let me explain how this would happen: (Though, I think that this will have some holes in it since I haven't watched the whole show yet, so feel free to tell me if you find one. This also might change after I finally watch the whole series)
After getting sucked into the Storm Shock portal, Vert went to the Blue Sentient homeworld. There, he meets Praxion, who then manages to convince/trick him into helping the diad free his Master, Krytus.
I have no idea how they manage to do that though.
But when he was released, he was severely weakened that he went into hibernation mode after a few minutes later. Praxion and Vert later found a way to help him recharge or something (Damn, I'm running out of ideas here). Still, Krytus is very weak and hostile and wary of the human.
The three remain stuck in the blue planet (The storm shock portal messed with Vert a bit so he doesn't go hungry for a good amount of days) until Krytus gets enough energy to make a portal (He can do that right?) to the Red Sentient Homeworld. At first he didn't want today bring the other two, but due to his current condition, he had to.
That's so far it, I've got other things but I need to work them out first:
Vert has really big father issues (He resents him because his mother wounded up getting severe depression after he disappeared and almost committed suicide if it were not for Vert stopping her and now lacks a father figure in his life.)
Krytus later knows about Vert's problem and uses it to his advantage.
Yes, Zoom, Stanford, Agura, Spinner and Sherman will still be included. They will also have problems of their own involving their families which their respective RS5 Counterpart will use.
Sage is instead rescued by Tezz, who managed to find a way out of the Red Sentient Moons.