Both games have a steep learning curve because they are such a radically different departure from any other games.

Once that learning curve is mastered, Sekigahara is the least complex game, by a fairly wide margin.

One offsetting feature, is that Coin games are semi-team games, so to the extent having a quasi-partner to talk strategy with makes the game easier, that’s a point in COIN’s favor. But even then there are a lot more moving parts to juggle in a COIN Game.