Fighting the same battle, personally. USB-C, by my understanding, can’t be split. The USB-C protocol negotiates the power requirements with the device, and a splitter would hose that up.
That said, if you’re trying to only do USB-C, my general preference is “shorter cables”. I use & like this little dongle:
https://www.bestbuy.com/site/insignia-magnetic-charging-dongle-for-apple-watch-white/6400042.p?skuId=6400042
which isn’t USB-C, but the Satechi version is:
That’s not a “fast charger” but it’s super-lightweight, and depending on the position of your charger, you might be able to plug the little dongle into it and sit your watch on it. Otherwise, the watch could charge from the iPad.
I also have & like these:
https://www.amazon.com/gp/product/B09CP6FJR3/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
They convert USB-C to Lightning, and the little rubber boot thing can be tied around your USB-C cable so you don’t lose it. That, plus:
https://www.amazon.com/gp/product/B086YYWL4T/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
is awesome. Again, this all depends on where your power brick lands. If you can count on an outlet on a counter, like in a bathroom, there’s a lot you can do with very short cables. Otherwise, rather than packing more and more cables I’d pack a good USB-C power bank and leave it charging wherever you’re staying. That, plus short cables, can be very useful if your device collection is limited.