You can restrict items to specific dimensions using the dimensions filter.

Dimension Blacklist (Ban in Nether)

Removes Water Buckets only if the player is in the Nether.

{
  "action": "remove",
  "items": [
    "minecraft:water_bucket"
  ],
  "dimensions": [
    "minecraft:the_nether"
  ]
}

Dimension Whitelist (Only Allow in Nether)

This prevents Flint and Steel from being used anywhere except the Nether. We use the not logic filter to achieve this.

{
  "action": "remove_interactions",
  "items": [
    "minecraft:flint_and_steel"
  ],
  "not": {
    "dimensions": [
      "minecraft:the_nether"
    ]
  }
}