n2gwtl I'm not sure I understand your question, but grapheneos.org and discuss.grapheneos.org use post-quantum encryption for HTTPS.
Go in devtools (you need to reload the page to display the results.)
In Chromium : DevTools (F12) > Privacy and security > grapheneos.org > Connection > Key exchange = X25519MLKEM768.
In Firefox : DevTools (F12) > Network > grapheneos.org > Security > Key exchange = "mlkem768x25519"
https://issues.chromium.org/issues/40910498
Is that what you're asking ?