I really haven't think about it before but I'll try to come up with something. I totally agree that Ponzu could most likely be a Conjurer based on her personality.
Before I state my guess about Ponzu's hatsu, let me list these things first: 01) I view Ponzu more like a healer than a fighter. 01) Ponzu is the type of character which will help others than hurt them. The proof to this is that she uses sleeping gas rather than relying on deadly weapons. Also her bees won't attack someone unless she screamed out of fear or if she collapses. 02) Not entirely sure but I believe Ponzu was named from a citrus-based sauce (thanks to the link [thechickensage]https://www.reddit.com/user/thechickensage provided). This may sound vague but this may relate her ability to food. 03) She used chemicals like sleeping gas in the Hunter Exam arc so her abilities will more likely be related to chemicals or sleep.
If I were to guess Ponzu's hatsu, I think she'll be able to Conjure a food pill which has chemicals in it that could put the one who took it to sleep. While being asleep, fatigue will be regained, healing recovery will be much faster than normal since the food pill was made out of Ponzu's Nen. In the 1999 anime Konta's (Gon's foxbear friend) son was about to die but Gon and Killua kinda speed up it's recovery by channeling their Nen to the little foxbear.
About the conditions for her food pill to take effect, these conditions must be met: 01) Ponzu must be within close range with the one who took it. 02) Ponzu will also be asleep until the food pill's effect disappears. 03) The effect of the food pill will range from 60-90 minutes (duration will increase or decrease based on the amount of Nen used). In that duration, Ponzu and the one who took it won't wake, therefore leading them both vulnerable (not really helpful in battles which makes this ability a little bit balanced). 04) Ponzu's food pill can only make the one who took it regain his stamina and speed up the recovery of wounds and therefore couldn't make up for the loss of blood or repair damaged organs/body parts.
There could be more chemical based ability possible but this is all that I can think.