Hi there!
Everyone knows the struggle to find Kids CC but if regular child CC is finding an oasis in a desert, finding child accessories is finding one particular needle in the sahara

The context is my sim family is high fashion, runway models, the talk of the town - papparazi on them everywhere.
However a really key component to fashion is the accessories - it highlights all the pieces together and signals intentionality to the design.

I want their son to be able to be fashion'd up just like their parents - Rolex's, gold rings and gold chains to wear by the pool.
Silver alternatives are fine, most things can be recoloured or worked around

However all I have found is Casio Baby G that I retextured the wrist part to look yellow and hashed. But the face is still digital. I can't even find where I got that from.
I hoped somewhere there would just be some repository containing conversions from adult to child but no such luck.
When I was aghast to find base game never came with sunglasses for kids, I was lucky to find a conversion from Sims 4 from Around The Sims.

Bonus points if you can find stud earrings for kids, but there are a few earrings for girls that I can convert to unisex (thanks for the directions) but ive only found cutesy ones

Anyone know a place to find for kids any metal rings, metal analogue wrist watches and any kind of necklace?

TSR have four cute necklaces for kids. This is all I could find. The majority of them are for Sims 4.

While accessories that fit children are limited to begin with, the unisex part is easy to achieve on your own. The child body and head are already unisex, so any and all CASParts for them are too and are only restricted by the flag set by the creator.
The appropriate flags can be edited with a tool like S3OC or EasyCASP.