There are alternative app stores on Android (Amazon and Samsung) but they suck and nobody uses them. It's a waste of time for Microsoft to pursue that IMO, and

There are alternative app stores on Android (Amazon and Samsung) but they suck and nobody uses them. It's a waste of time for Microsoft to pursue that IMO, and even if they did it, it wouldn't be a viable replacement for the Play Store. As for Edge, the mobile browser doesn't use Microsoft engine. Edge on Android is based on Blink but has Windows desktop integrations. Personally I use Edge on my laptop because it's much lighter on battery life and I rarely encounter compatibility issues with sites.