Here's a fine online version of Frank Chadwick's hex and counter game, Battle for Moscow, a game of the 1941 German attack that came up short.
https://oberlabs.com/b4m/The original game was an introductory game with great replay value, IMHO. The online version can be played solitaire/hotseat, you as German vs. Russian AI or you as Russian vs. German AI. Once you get the interface down, games take less than an hour.
I play a lot and usually beat the AI, playing solitaire for close games. The designer has plans to have a remote play option, but that's lots of work. Don't hold your breath. But do try it.