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Probably something like this.
Also, Intrepid Sword should boost both offenses and Dauntless Shield should boost both defenses.
Zamazenta gets Recover and a good support movepool. Zacian gets a good special attacking movepool.
Fairy/Steel is the best defensive type in the game, so it makes more sense for Zamazenta to have it, and Ghost/Fighting is the best offensive type, so it makes sense for Zacian to have it. Thematically, shields are hard like steel and swords are used for fighting. Ghost and fairy aren't thematic at all, but fairy wasn't exactly thematic for Zacian in the first place.