I want to solder the relay expansion directly to the omega2+ due to needing for a smaller casing.
My Plan is to use input USB 5v via the regulator to 3.3 so that the onion is powered. (https://docs.onion.io/omega2-docs/hardware-prep-no-dock.html)
I've found the schematics for the relay but I'm bit confused because I don't know which pins are only needed for the relay and which are unnecessary.
Which of the conedge pins are actually used because there is for example 3 times ground?
Here is my rough concept: