Hide HealthBar

This mod lets you independently hide entity health bars and damage numbers for players and NPCs.
As a server mod this applies globally and a client can't bypass it.

{
  "targets": [
    { "target": "players", "hideHealthBar": true, "hideDamage": true },
    { "target": "npcs",    "hideHealthBar": true, "hideDamage": false }
  ]
}

See /hhb for ingame options