Shure SE215

Not sure exactly what you mean by this....If you mean 'will the headphones out give you everything in the chain' then the answer is yes.

It wont matter if the pedals are before the Kemper or in the loop ( once the loop is switched on as a stomp )

I use similar Shure's live and get a line back from the desk with my vocals mixed in to my wired in ear pack. You will need an in ear pack to drive the headphones unless you just want to hear guitar straight out of the ' headphones output ' on the KPA.

I take my monitor out to a separate channel on the desk which is fed back to my ears pack with my vocals to allow me to adjust the Kemper separately from my vocal on the fly during a gig.