Potion of Shirt-On-Backwards
The imbiber of this cursed potion cannot put their shirt on the right way. Normally this is just embarrassing and can be hidden under a cloak or shawl. Unfortunately the effect extends to armor, and affected's armor class is always treated as a class lower. Also may mess with some high-necked sorcerer robes.
Teleportato
Eat this whole tuber raw and you'll be warped back to where it was grown. The crops are a little weaker and meandering each year. Cooked into a meal it invokes strong yearning for that place instead and grants everyone who partakes advantage on checks to navigate there for a month.
Knobgoblin
A leering, verdigrised codpiece that bestows all the advantages of a ring of protection if worn proudly and obviously. Its facial expression shifts slightly to match the wearer's subconscious when not observed. Once per week it can be used to cast magic missile with a suitably obscene set of somatic gestures.
Pom de Terror
Planted in a garden, this root will flourish with almost no care. In fact, it will grow luxuriously when other plants near it flounder, and produce far too many offshoots. Within a year, it becomes the basis of farming within the hex it was planted in. And then it withdraws its nourishment -- the roots become bitter and underwhelming, providing just enough to keep people and livestock moving but not nourished. Soon they advance to their neighbor's farms, sickles sharpened, hungry grins waiting. The Pom de Terror is upon them.
Glaive of Mutilation
On a critical hit, this outlandish polearm deals an outlandish amount of extra damage (6d, maximum x 3, +3, whatever comes up to the borders of the system without being vorpal).
You Tuber
A wriggling 5-pronged root. Cut yourself, dribble some blood on it while you whisper, and plant it somewhere dank. Come back in a year, and unearth a simulacrum fascinated with your whispers and gaining approval, though not necessarily yours. It's a crappy copy of you with expertise in one of your skills, no loyalty, and an intense desire for fame. Good luck.
The Book of Making Ready the Way
This spellbook would look at home on any academic's shelf. A leather-bound, tastefully-gilt vellum volume. The internals are fairly common observations on the night sky and weather patterns, with a lot of internal references. Like, a lot. Holding certain pages that reference each other forces one's fingers into the correct patterns, and there lie the book's spells of abjuration and, with practice, hidden names.
If the Book of Making Ready the Way is used as a material component in any ritual that requires tracing a geometry, that ritual is a level more effective due to the precise placement of angles and points the book engenders.
Bolus Bolas
Rank and stinking bolas with a wet mass bound on each end. They deal escalating acid damage to a creature bound up in them for a few rounds until they burn themselves out.
Given a pair of rations, they can recover or even reproduce themselves.
Trickledown
This magical saber is forged of pure reaganite. On a hit, compare the wielder's lifestyle to the target's (luxury > wealthy > modest > poor > squalid): Trickledown deals additional damage for each step the wielder is above the target (a d6, or a +1, or bump the weapon die, depending on the system).
Additionally, the wielder has advantage on any Deception-style checks to convince someone a plan is in their best interest, or to stoke fears of a nebulous "they", so long as the notion is mostly lacking in details.
Trickledown is a mildly intelligent weapon with a weak and mumbly ego wrapped around a blistering Neutral Evil core dedicated to the golden rule: He who has the gold makes the rules. It will nudge its bearer to acquire wealth at any cost, but preferably at someone else's cost.
The saber's goat-skin scabbard, Throat, is also mildly enchanted. Once per month, it can be used to cast commune, but it can just say no. It's said that on lonely nights, some adventurers have put the scabbard to unusual uses with remarkable success, but this is likely merely a rumor.