Original intent is lost, along with the old WiaB and the old SG. The assumed original intent is not the current intent or the future intnet. To wonder what might be which won't happen because of the ToS Ocean needs to stick to won't persuade the people Ocean needs to keep onboard. Nothing needs to change in the scrip we hae of SG fro Sasha to simply be a Petrova. For her to be part Zane, Ocean will need to change the script and potentially add in plot lines in 2030 of SG Season 1 right up to wherever he gets to by the time Wiab Is published. And the same for all the other potential crossover choices. I don't think that's a useful way for Ocean to spend time.
Of SG, what prevents Bella, Elsa, Mila, Nadia, Nia, Vanessa, or Zara from being William's wild oats (or Leia's genes)? The only thing is who Nika's daddy might be. Of these we know nothing for certain. If any of them were Leia's, it's still the same situation. The Frohns, Sonya, Amber, Marla are the only ones definitely not.
The only problem is technical in regard to whether it's too much work to transfer WiaB saves meaningfully. Season to season makes sense, because Ocean hasn't developed the subsequent seasons before so it can be implemented on the fly, in an almost linear fashion. Then SG will eventually be done, and it's save can easily be ported to the next game. THe technical issue is that WiaB won't befinished before we're in the third season of SG, which will bake a lot of things into our memories.
I'm honestly not certain about who is or isn't a Zane via sticky tryst. WiaB will clear up a lot of things for SG once we find out those bits of knowledge regarding the new thrust.