OK, I track this shit. So sorry for the response.
Yes, IF they know they are at sea. Now who owns them? Who is selling and buying are the tricky parts. Once a ship turns off its transponder, and they are not supposed to do that, they go dark. So only way to track is visual or if they communicate and NATO is listening. The shadow fleet is large and not only used/operated Russians.
Finances can be tracked, but that is like finding a needle in the haystack. Have to know where to start looking. So buyers/sellers just create new entities they use for a few specific deals. A lot of these groups cut their deals in Dubai.
One thing that happens, and there is a lot of evidence, is at sea transfer. So Ship A (under sanctions) runs out of Russia/Iran/Venezuela. The oil is already paid for.
Once at sea they meet up with Ship B (not sanctioned), they transfer, and Ship B takes it to port.
The hardest part of all this for the sanction busters are the Ships. It is a pain to reregister every few trips, so they press their luck. It would be interesting to know the last port of call for these two ships. maybe not blow them up? Find the trends and follow the leads.
Hope this is better than a NOPE.