SuperTokens is an open source authentication solution offering features like: Different types of login: Email / password, Passwordless (OTP or Magic link based).

SuperTokens.com

Is there anywhere where I can access google username after signing up, for example in thirdPartySignInUpPOST?

Hey! Yes. There is. That’s exactly the right place

https://supertokens.com/docs/thirdpartyemailpassword/post-login/getting-provider-access-token

Thanks. Just to make sure scope info isn't prefetched I have to do it myself in override?