Heyman in WCW wouldn't have worked. Period. Heyman, as a booker, needs autonomy, and he'd have immediately butted heads with Turner brass (especially Standards & Practices) to the point where he's looking for a new job within a few months. That's not even in terms of the sex and violence aspect that Heyman thrived in, but more how he'd be putting guys like Hogan, Flair, Savage, etc. on the chopping block as soon as he could.
Bluntly put, Heyman taking Russo's WCW spot hurts the business more than what happens, and WCW's demise is accelerated because most of the Turner contracts become worthless but costly.
Now, let's say that happens, and he's looking for work in early 2000. Well, there's this company up north that he's had a good rapport with for a few years, and he ends up working there off/on for 20ish years in our timeline, and they're on some form of cruise control after Russo leaves (this is assuming Russo still leaves)...
Basically, we get the awesomeness of WWF in the year 2000, but it has an even greater emphasis on workrate, episodic storytelling involving logical twists and turns, and maybe a Light Heavyweight division that crosses paths with the Hardcore division to become its own thing.
I'd love to have been able to see what Heyman could've done with Goldberg's rehab, Bret Hart, and DDP. Of those three, I feel Page would be the one most willing to work with Paul E, because he'd proven time and again that he'd do his best with whatever's handed to him.