Add Spell effect - Tasha's other worldly Guise

This items ad the effect of the spell Tasha's Other worldly Guise which can be used to switch on and off for the character sheet. 

Spell description: 

Uttering an incantation, you draw on the magic of the Lower Planes or Upper Planes (your choice) to transform yourself. You gain the following benefits until the spell ends:

• You are immune to fire and poison damage (Lower Planes) or radiant and necrotic damage (Upper Planes).
• You are immune to the poisoned condition (Lower Planes) or the charmed condition (Upper Planes).
• Spectral wings appear on your back, giving you a flying speed of 40 feet.
• You have a +2 bonus to AC.
• All your weapon attacks are magical, and when you make a weapon attack, you can use your spellcasting ability modifier, instead of Strength or Dexterity, for the attack and damage rolls.
• You can attack twice, instead of once, when you take the Attack action on your turn. You ignore this benefit if you already have a feature, like Extra Attack, that lets you attack more than once when you take the Attack action on your turn.

Notes: Immunity: Necrotic, Immunity: Radiant, Bonus: Armor Class, Bonus: Speed (Flying), Damage: Melee Weapon Attacks, Damage: Unarmed Attacks, Damage: Natural Attacks, Bonus: Extra Attacks