From the settings page.

* crosspost discussions to nostr
* requires NIP-07 extension for signing
* we use your NIP-05 relays if set
* otherwise we default to these relays:
  * wss://nostrue.com/
  * wss://relay.damus.io/
  * wss://relay.nostr.band/
  * wss://relay.snort.social/
  * wss://nostr21.com/


kepford

No the other way around.

* You add your pubkey to SN settings.
* Change your settings to cross post
* Post a discussion on SN
* SN will ask your browser extension perm to cross post.  Alby or nost2x for example
* You post on SN is published to the relays as long form content.