Well, then, in any final legal agreement, I would impose that they're going to have to provide restitution and replace those vessels.
There is no chance that the EU or the US will try to impose such conditions and, even if they did, Putin would just laugh at them. As long as it is Western rhetoric against Russian armor, Russia will win. The West needs to at least take deterrent actions such as stationing a sizable logistic and humantarian presence in Tbilisi and a small military force and equipment in Ukraine.
Why? I don’t condone their action, but it really is the Russians inflicting their version of punishment and humiliation on the Georgian President and his armed forces. Do you honestly think that they are going to leave in place all captured Georgian forces equipment completely as they found it? No army is ever going to do that. The tactics are disable, destroy or keep it themselves.
Under conflict those naval boats are legitimate targets. When the U.S. pulled back out of Iraq in 1991 they blew up and disabled Iraqi aircraft on the airfields that they over-ran.