As per the latest documentation, the `graphql` wire adapter is not supported in Experience Cloud sites. However, I have tried it in my developer edition org, in Aura Experience Cloud sites and it works absolutely fine. Only in LWR Experience Cloud sites, the import does not work and routes to the error page regardless of LWS enabled or not. Is this an undocumented behavior? Can we safely test and use `graphql` in sandbox and production Aura sites?
Officially, until GraphQL is fully supported in both Aura and LWR Experience Cloud sites, we generally have taken the stance to document that it is not fully supported in Experience Cloud sites. However, as you stated, it does work for Aura Experience Cloud sites. This should work in sandbox and production Aura sites without issue. We are working to bring support for LWR Experience Cloud Sites as well, but I don't have a targeted release for that quite yet.
According to the Winter 25 release notes it is now supported in Experience Cloud
https://help.salesforce.com/s/articleView?id=release-notes.rn_lwc_modules.htm&language=en_US&release=252&type=5#:~:text=the%20graphql%20wire%20adapter%20is%20now%20supported%20in%20experience%20cloud%20sites. "The GraphQL wire adapter is now supported in Experience Cloud sites."
