Re: M5 StickC Plus, You can get suitable proto boards:
https://thepihut.com/products/m5stickc-proto-hat
https://thepihut.com/products/new-mini-proto-unit
The first is probably the best to use because the Grove connection for 5V is OUT (so not suitable to link to MK14 5V). The other connector allows 5V IN (to preserve/charge battery). The only hitch is that the output pins will need to be changed (G32/33 on Grove, G25/26/0 on 8 pin).