Do p-channel FETs mirror the n-channel $I_d-V_{gs}$ graphs?

P-channel FETS will have the n-type and p-type semiconductor regions reversed with respect to n-channel, so the $V_{gs}$ bias will be opposite for the same operation (current still flows from the drain to the source). Yes, the $I_d$ vs $V_{gs}$ curve will be the mirror image, with increasing $I_d$ going up to the left.