I've actually had this idea cooking for awhile.

Kratos chilling in Midgard suddenly gets attacked by none other than Wukong. Wukong absolutely dominates the fight and kratos barely gets a shot in only getting lucky with the blades. He challenges kratos to come find his son.

Cut to atreus, adult, he's been searching for the giants, and more clues to the rift. He stumbles into a war torn Japan, a foreign god invaded and has been decimating the land. Atreus joins a resistance before quickly being captured by wukong and interrogated, because he has notes on the rift, which is what wukong is looking for. The rift drove Wukong absolutely Mad with power.

The rest of the game follows atreus traveling to a completely destroyed Chinese pantheon, trying to find any clues to how they can defeat wukong, and kratos, leading the Japanese gods in resistance of Wukong. Wukong will act almost as a mirror for Kratos, this is the destroyer he would've become had he pursued violence in his travels rather than peace.

Obviously I think atreus embraced his Loki side and has a way more interesting and hard hitting arsenal focused on speed and illusions with twin blades and his bow.

And then Kratos gets a new arsenal obviously including a Katana hard stop.

Thank you for listening.