I’ll make a quick list of what I’m sure of:
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - NO
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (but fails sometimes for some random reason, always works on crouching though)
cl.HK > cl.MP - YES (VERY deep only)
cl.HK > cr.MP xx KRK - NO (I think)
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES (when cancelled into H Danku, one of the hits whiffs strangely enough)
cl.HK > cr.MP xx KRK - YES (may not work on crouching)
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES (if cl.HK counterhits, cr.MP bust be exchanged to cr.MK)
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES ( think)
cl.HK > cl.MP - YES (deep only I think)
cl.HK > cr.MP xx KRK - YES (I think)
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES (VERY deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - Uncertain
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (crouching only)
cl.HK > cl.MP - YES (very strict, you should really try to go deep)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - NO (may work on crouching, I’m not sure)
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES (I think, may NOT work on crouching)
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - NO (works on crouching though I think)
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (I think)
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES (only on crouching)
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (as reliable as against Akuma I think)
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - NO
KRK xx FADC > H Danku - NO
KRK xx nj.HP - NO
(what a fucker)
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (crouching only)
cl.HK > cl.MP - YES (deep only)
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (crouching only)
cl.HK > cl.MP - YES (remember to go under his uppercuts before punishing to get deep enough, his front landing animation pushes you away)
cl.HK > cr.MP xx KRK - YES (do same against his uppercuts here)
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES (crouching only) (if cl.HK counterhits, cr.MP bust be exchanged to cr.MK)
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - YES
cl.HK > cr.MP xx KRK - YES
cl.HK > cl.MP - NO
cl.HK > cr.MP xx KRK - YES
Haha I knew more in my head than I thought. 
Just as a sidenote, those have NO on the cl.HK > cl.MP combo may acutally work if the opponent’s crouching, but I’m unsure of this.