Hopefully not a stupid question, but is there any reason why you couldn’t proxy the new WSS sculpts as GNW Swedes or Russians?

Ray you can to some extent. Most musketeer and cavalry figures coud be used for the bulk of the Russians - the musketeers and dragoons. But the Russians have some units wear the kartuz type hat and there are some other specialist types not in the WSS range - cossacks certainlt and streltzi maybe. You have similar problems with the Swedes but with the extra complication that they are in uniforms similar to those of the SYW period generally - i.e. they have turnbacks.