Goblin Haberdasher

• WOTC Official Reminder Textofficial rules
  Menace — This creature can't be blocked except by two or more creatures.

• WWizards of the Coast2020-02-29
  Official Ruling
  A hat is a garment worn on the head that’s not part of another garment. Hoodies, for example, are not hats. Items that only cover the face and not the top of the head, such as a face mask, are also not hats.
• WWizards of the Coast2020-02-29
  Official Ruling
  If the card represents multiple creatures and at least one of them is wearing a hat, the creature will have menace.
• WWizards of the Coast2020-02-29
  Official Ruling
  The creature that the card represents must be wearing a hat to have menace. A background character or a scale bird wearing a hat wouldn’t count. (But scale birds in hats! Adorable!)
• WWizards of the Coast2020-02-29
  Official Ruling
  If the creature is a hat, it won’t have menace, unless it itself is wearing a hat.

Rulings via Scryfall