You don't see the function because it's not there. The only confirmations from any other logging system that QRZ honors are those from LoTW Dave W7UUU
But I don't think it will recognize the confirmations. I doubt it. It can generate new confirmations if the other guy happens to use both systems.
To elaborate on this, QRZ honors LOTW confirmations only in the case of a LOTW>QRZ direct download only. QRZ does not respect ANY confirmations in ADIF imports at all, even if the ADIF came from LOTW.
Because they (both) are not set up to do that. You'll have to do it manually. Confirmations will not count for QRZ awards.
This is just me talking, but the problem, I think, is that eQSL has been proven to be too easy to spoof. There are too may "fake" QSL confirmations in there mostly due to the lack of them using a "double-blind" system to ensure that the confirmations are real and correct. ARRL and QRZ want to maintain higher standards that what is offered over at eQSL. Again, in my opinion, it's just that simple.