Apple Watch Charging

I have two third-party multi-plug charging cables. They each have a USB-A plug on one end and an Apple Watch puck and two other cords on the other end, one with two Lighting connectors, the other with one Lightning connector and one micro USB connector. Those cords work fine with a series 4 Apple Watch but won't charge a series 7 model. I understand that a series 7 watch likes the higher current that a USB-C charger can provide, but I expected the old cables to still charge a series 7 watch, although possibly slower. Is something going on that I'm missing? Are there any multi-connector cables that work with USB-C?