I just finished setting mine up and i kinda had the same problem. i only got the 13in macbook pro so i only have two thunderports but i'm also using something similar to what the first commenter posted.

VANMASS USB C Hub, 7 in 1 USB C Adapter with 5K@60Hz Thunderbolt 3 Port, 4K HDMI Port, 2 USB 3.0 Ports, SD/TF Card Reader, 87W PD Charging Port for MacBook Pro and MacBook Air 2018/2019/ 2020(Silver)

it has two thunder ports that you can use for your a) charger and b) ethernet adapter. there are similar that have the ethernet port within the hub but i don't need that so i wasn't looking for it

i have ^that^ plugged in for my HDMI cable (separate monitor), my laptop charger and for this

AUKEY [Upgraded] USB Hub 3.0, Aluminum 7 Port USB 3.0 Data Hub with 12V/2.5A Power Adapter, 3.3ft USB Cable for MacBook Air, Mac Mini, iMac, Laptop, PC, USB Flash Drives, Hard Drive (Silver)

this is a splitter but it's powered through an outlet and then connected via usb to the hub that is in the first link. I have my external HD, MPK Mini II, Pioneer DDJSX2 and focusrite scarlett 2i2 connected to the *powered* USB hub and haven't noticed any delay issues of the sort. I feel like the USB Hub being powered on it's own before even being connected to your laptop helps with it? i did some searching on the answer and everyone basically said the same

anyways i hope this helps. this had helped me minimize my wiring and such. hope it can help you!

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