I’ve seen wechat pay and other features used throughout Asia, though to a much lesser degree than localized services. That is to say, it’s still a “super-app” in all markets. Which services are supported in each market is up to the real-world marketplace, not necessarily the Google Play or App Store. As far as I know, the international version of wechat still has most of the same capabilities (and privacy concerns thereof) that the domestic China Weixin app has.

It’s a good question why western super apps haven’t taken off yet, and I feel like most users prefer fractured services until now. For example, Facebook had marketplace and messenger as part of its main service for years. Then, it decided to fracture them off into separate apps/services.

WeChat and other composite apps are already on the stores, so I don’t see why others also wouldn’t be allowed.