Estonian, Latvian, and Lithuanian power systems synchronised with Europe

Yes, in the Suwalki Gap (border between Poland and Lithuania). Until this point, the connections were HVDC including to Sweden and Finland (across the Baltic Sea).

> Will they be buying electricity from Europe or selling electricity to Europe?

They already participate in the EU electricity market (through the HVDC lines), some hours buying cheap power from clean sources, sometimes selling expensive non-renewable power.

Yes.

(Beyond the fact that they are _in Europe_, generally this sort of thing goes both ways depending on the time of day).

    1. no ability to sell electricity to baltics
    2. no ability to disrupt baltic grid
    3. managed to island russian enclave of koingsberg, giving control of its energy supply to the baltics (they could now cut off its gas)

> All electricity interconnections with Russia and Belarus have been permanently disconnected.