Amulet of the Fool

This isn't really a bad item, it's just not terribly interesting or well-fitted to 5e standards.  The only pure stat items I can think of in the game are STR belts, and tomes that are permanent stat increases.  It's hard to keep track of multiple little +2, +1, +2 here and there bonuses to stats, and easy to end up with confused character sheets.  That doesn't necessarily mean you can't have +2 raw stats, but something to keep in mind when making items.  

The interesting part though, that's harder to address.  In general I'd say add a social effect like "once a day, you can say a line guaranteed to make all who hear and understand erupt with laughter".  Mostly it just needs a thing that will make it feel like more than points on a sheet - a thing that makes the player remember they're wearing it.