Going just by a feeling (or in some cases, past "excuses" from the RAW)

Artificer: (Chaotic) Neutral
Barbarian: Chaotic Neutral/Evil
Bard: Chaotic Good/Neutral
Cleric: Any (same as their deity)
Druid: Any Neutral
Fighter: Lawful Neutral
Monk: Any Lawful
Paladin: Lawful Good
Ranger: Chaotic/Neutral Good
Rogue: (Chaotic) Neutral or Chaotic/Neutral Evil
Sorcerer: Chaotic Neutral
Warlock: Lawful Evil
Wizard: True Neutral