> React Native doesn't even use v8 engine

Are you saying you would use React Native with a language other than JS?

Engines other than v8 exist. React Native uses Hermes or JavaScriptCore (Apple/Safari). [0]

Other engines include SpiderMonkey (Mozilla/Firefox) [1] and QuickJS [2]

[0]: https://reactnative.dev/docs/javascript-environment

[1]: https://spidermonkey.dev/

[2]: https://bellard.org/quickjs/