ActuallyAdditions/src/main/resources/assets/actuallyadditions/models/item/item_worm.json

{
  "parent": "actuallyadditions:item/standard_item",
  "textures": {
    "layer0": "actuallyadditions:items/item_worm"
  },
  "overrides": [{
    "predicate": {
      "actuallyadditions:snail": 1
    },
    "model": "actuallyadditions:item/item_snail"
  }]
}