Denatured alcohol will remove both acrylic and polyurethane . Soak them in it and scrub it off with a toothbrush .
Isopropyl ( rubbing ) alcohol will easily remove acrylic , and probably the Vallejo poly . If you have some 91 or 99% isopropyl , soak them in it to see . Even the 50% solution will work , it's just not as fast .
The poly should require a bit longer , but it's probably a poly / acrylic resin so it might come off fast .
Acetone and lacquer thinner ( which is usually mostly alcohol and acetone ) also - - since it's a metal figure and you don't have to worry about melting the plastic of a polystyrene figure .
Alcohol won't damage polystyrene .
Also Xylene ,and Ethyl Acetate ( often sold as " MEK Substitute " ) , but obviously the alcohol would be the more " benign " route .