Board Game Arena

Such as the tick, cross & money required icons. I just want to turn them off personally so I can learn resource costs/chains etc, I'm not questioning their purpose or benefit in general.

I don't think you can unfortunately. I understand your need but online the main concern with online players is effectiveness, which justifies the fact that the game calculates costs for you. If you want to learn, the best way is IRL with someone good at the game. Plus, you can play Armada, where costs get really complex and interesting.