Yes!
First you can chain swaps (even accross different providers eg swapmarket.github.io nostr:nprofile1qqsrtm03p9knckg63gyjk74yxy3u9e28vgxgr8ju3jk9dfz0ph7qrjqpr9mhxue69uhhyetvv9ujuumwdae8gtnnda3kjctv9uq32amnwvaz7tmjv4kxz7fwv3sk6atn9e5k7tcppemhxue69uhkummn9ekx7mp0fns9n9 )
onchain - LN - LN - onchain
Second is the actual coinswap protocol aka teleport transactions under development:
CoinSwap looks like what I'm looking for!
For my case further constraints:
- no LN involved, and
- no onchain linkage between the two parties after a swap.
The use case I'm thinking about is a marketplace for swapping mined 'clean' coins for other coins, for a small premium. LN might be cumbersome because of the amounts. CoinSwap seems to be able to solve this. Thx!
I was brain-storming how to achieve this using adaptor signatures, but as I can see there is a solution like that already (Ruben Somsen).
https://gist.github.com/RubenSomsen/8853a66a64825716f51b409be528355f
