For getting a custom speaker tap built, would you guys recommend to get a 4-pin XLR adapter or rather a 2 x 3,5mm adapter to hook up the Susvaras directly?
The XLR adapter will have the advantage of connecting different cans later on such as TCs...
is there any specific PIN configuration to be considered for the XLR option or just standard female 4-PIN XLR?
I'd go with the 4 pin xlr for convenience and versatility. Unless you're absolutely sure youre going to be happy with the cable material/selection/pairing with the susvara and don't intend to use it with anything else.
Another option is to get a speaker tap adaptor box made. I ordered one with zynsonix recently and i believe it will be sent out to me today.