I’m a fan of these guys:

https://www.amazon.com/dp/B0CHHZTGJR

Power is passed through from either connector, so it’ll work on 5v or 12v strings. And it’s got two output channels. It’s only an ESP8266 inside, but that works fine for my needs.

For a slightly more DIY approach, try this one:

https://wiki.vdbx.io/product/flip_c3

Has everything you need to give it some sort of power and get the requisite data signal out.