05-08-2020, 08:53 PM
Your plugin could do something like teleport the player to the top of water constantly, or set the blocks underneath their feet to be tinted glass or blue wool. (I'm not aware of any method to tell the client that water has collision, apart from modified clients.)
For hardness, the plugin could listen for HOOK_PLAYER_BREAKING_BLOCK and family and then determine based on its own calculations of hardness how long it should take to break.
For hardness, the plugin could listen for HOOK_PLAYER_BREAKING_BLOCK and family and then determine based on its own calculations of hardness how long it should take to break.