TSMC65 allows two types of variation analysis.

1. Intra-die variation:

for the intra-die variation you have to select mismatch only in monte carlo window.

1.1 for normal mos: you have to enable tt and stat_mis with all moses are xxx_mac

1.2 for lvt mos: you have to enable tt_lvt and stat_mis_lvt with all moses are xxx_lvt_mac

1.3: for hvt mos: all lvt to hvt in 1.2

2. Inter-die variation:

for the intra-die variation you have to select process only in monte carlo window.

2.1 for normal mos: you have to enable mc and stat with all moses are normal. Dont enable any tt or ss or ff or any corners. it worked for me.

2.2 for lvt mos: for this i followed as in intra-die, so it could be mc_lvt and stat_lvt. there is mc_lvt, unfortunately there is  no stat_lvt in TSMC65. it didnt work for me. I tried with mc_lvt and stat (it worked!!!)