Treasure in a Fey Lord's lair?

[PiperThePaladin]

The self-styled Robber King, a self-important, grandiose Fey Lord of comparatively little power. She has been pilfering items from the various planes for years, though nothing of enough power to draw the attention of her more powerful neighbors. Her lair is in the Feywild, and I'd like her collection to contain a mix of helpful, unimportant, and dangerous/cursed items, with no way for the party to easy tell which is which. Ideas?

[Xihirli]

If you want to make like 80 magic items with minor benefits there’s some here.
www.lordbyng.net/inspiration/results.php

[KorvinStarmast]

The self-styled Robber King, a self-important, grandiose Fey Lord of comparatively little power. She has been pilfering items from the various planes for years, though nothing of enough power to draw the attention of her more powerful neighbors. Her lair is in the Feywild, and I'd like her collection to contain a mix of helpful, unimportant, and dangerous/cursed items, with no way for the party to easy tell which is which. Ideas?
1. Wand of Wonder.

2. Cursed Ring of Silence: cursed ring that acts as ring of spell storing except that on the roll of a 1 on a 1d20, it casts silence on the wearer rather than casting the spell. (Or a 1 on 1d12 ...). Identify and Detect Magic cannot detect the curse. It requires Legend Lore or a very high DC check, Arcana, to understand the problem. Remove curse to break attunement.

3. Boots of the Dancing Fool: normally behave as Boots of Elvenkind, except when making a Stealth check, roll a 1 on a 1d12 and the roll has disadvantage, and the sound of scuffing is distinctly.

[Brotherbock]

What about a sword that is entirely arbitrary about whether it likes the wielder or not--if it does, it's a +whatever. If it doesn't, it's cursed for as long as you possess it.

Ooh, ooh...a Mallet of Luck! You can use it to bestow a +Whatever to saves/att/ability/etc, but you have to hit someone with it for 2d6 damage to give the benefit.

A Dagger of Empathy. After you hit somebody with it once, you can deal damage to them by dealing damage to yourself. You automatically damage yourself (still have to roll for damage), and you both take the full damage. If you do something to avoid taking the damage, they also avoid taking the damage. (Maybe build in a recurring attempt to save to break the connection, otherwise you can wreck a spellcaster.)

[Brotherbock]

3. Boots of the Dancing Fool: normally behave as Boots of Elvenkind, except when making a Stealth check, roll a 1 on a 1d12 and the roll has disadvantage, and the sound of scuffing is distinctly.

Boots of Walking. That's just what they do. Increase normal speed by 5. But every day, there's a cumulative 5% chance that they will walk all over you, delivering 2d10 points of damage.

[BreaktheStatue]

XGtE has the common magic items, which are (sort of) helpful and unimportant.

[ImproperJustice]

If you can find it out there somewhere, seek out Paladium Fantasy RPGs list of fairy foods.

It’s just a whole set of foods, beverages, and sweets that provide various pun related maladies and benefits.

Our group’s all time favorite:

The bag of mixed nuts: Consuming a handful of the delicious nuts results in the consumer obtaining 1d4+1 randomly determined mental disorders for 24 hours.

[Wryte]

A few that came up in a campaign I played in last year:

Rock of Gravity: This polished stone detects the presence and orientation of gravity. As an action, the wielder can let go of the rock. The direction it falls in is the direction of the local gravity.

Shield of Protection: This magical shield automatically moves to protect... itself. While wielding this shield, when an attack roll against you fails by a 1 or a 2, the shield uses your reaction to move itself out of the attack's path, causing the attack to hit you instead.