If you don’t mix your KYC bitcoin they pretty much always know when you do anything with bitcoin. All the transactions are children of that initial KYC exchange transaction. Do be aware though, when you coinjoin KYC bitcoin they see that you did that. At best they will see you moved your bitcoin and whoever got it then mixed it. But I think it’s important to acknowledge that mixing bitcoin isn’t illegal, it’s actually just the proper way to use bitcoin on chain when you’re dealing with KYC bitcoin.