Do I need Meta Capi setup via GTM if I am using Stape Capi gateway?
not necessarily, so long as your Pixel is implemented and confgured (by any means) the Gateway will connect to that.
yes i have implemented pixel via facebook plugin for woocommerce and CAPI via gateway. I was not just sure whether I should also do it via sGTM
Gateway and sGTM are mutually exclusive, you never need both.
facebook plugin for woocommerce and CAPI via gateway
sounds OK to me
Thanks you are awesome