The PT92 I have seen have the portion going into the holster identical to the typical 92FS. Watch for whether there is an accessory rail on the dustcover.
I have used IWB holsters as shown above, without retention, except for the pinch at the trigger guard. They worked well for awhile, then the plastic got tired, and it did not retain any more. Now I will only use one with active retention (usually a thumb-break), such as the Bianchi 3S IWB for the 92:
https://www.midwayusa.com/product/1336216812
Don't go hog wild with the retention. I saw an internet advertisement for some Police-surplus holsters, with level III retention. The cost was nominal, so I bought one and found out why they were so cheap. I could not get a pistol out of the holster without using at least two hands.