Somebody will see you sent Bitcoin to an exchange that doesn't do KYC. Or received Bitcoin from an exchange that doesn't do KYC. That's it.
Discussion
Right, so let's assume the nonkyc exchange is compromised. In theory they could trace that this user traded btc for xmr, and then that same user traded xmr for btc, right? Or am I misunderstanding how these exchanges hold records? Basically I'm trying to figure out if once I trade to xmr if I need to do a single transaction before going back to btc to have truly private cold storage. I am considering using this samourai beta for the swap if I can figure out the fee structure.
If you're concerned about somebody being able to deduce that you interacted with Monero at all, then yes this could be a potential problem.
Use two different exchanges for each swap.
Exchange A will know you swapped 'X' Bitcoin for Monero, but not know where it went.
Exchange B will know you swapped 'X' Monero for Bitcoin, but not know where it came from.
If you want to eliminate the small chance of collusion between exchanges, paranoia dial to max, do both swaps p2p with different peers using Bisq, Robosats, and/or LocalMonero
You can send everything to XMR for the first swap, but for the second swap - send different amounts to BTC and stagger the timing. A few days maybe.