This represent are two styles of armors born from different doctrines of combat. The western styles minimized burden of carry, with flashy designs and ornate helmets. The eastern one maximized protection, with a more distinctive sober look.
Wanna know more about them? Those illustrations were commissioned work for Gunsen History's threads about Japanese armors and military history! Check them out here:
East: https://www.deviantart.com/users/outgoing?https://twitter.com/gunsen_history/status/1683385539150397442
West: https://www.deviantart.com/users/outgoing?https://twitter.com/gunsen_history/status/1691002513346998272