It is required for the victim to flash a light-red color when damaged (since the attacker cannot know if they are dealing damage without relying on sound or knockback) while using the shield (but without disabling the shields if they are crafted or obtained). Is it not possible to disable his functionality server side while maintaining the block animations among all players?

Additionally, an option to disable spam in the console when a player uses sword blocking
(00:20:39 [INFO] [OldCombatMechanics] Restoring items for player Nameless: Current offhand: ItemStack{SHIELD x 1, TILE_ENTITY_META:{meta-type=TILE_ENTITY, Damage=27, blockMaterial=SHIELD}}, Stored item: ItemStack{AIR x 0})
-would be helpful. I don't think it's strictly necessary to have those messages activated (they work even with the debug option turned off).

edit: also, players with absorption who are shield-blocking do not produce any damage sounds