Interestingly, when I was working as a manager in a hotel (going back maybe 6 years ago now), I once hired someone with a tattoo that was slightly visible on her neck. I got an absolute bollocking from the hotel manager because she wasn't the right 'fit' for us. Anyway, the girl turned out to be an absolute superstar - a real asset to the hotel. She even won employee of the month (out of a staff of 100+) a couple of times while I worked there.Very interesting question, and a challenging position to be in!
Unfortunately, although City law has (generally) made leaps and bounds in terms of acceptance etc in new recruits, there are still many people (often older Partners etc) who don't have such nuanced and open opinions about things- especially something like pole dancing which obviously falls outside of D&I drives etc. I myself have been in a similar position (albeit not with pole dancing- I don't think I'm quite 'cut out' for that...) with hobbies that might have preconceived notions attached to them, and I would typically moderate them in some way. The closest parallel that now affects me would be the fact that I'm quite heavily tattooed. Both my arms are in the process of getting sleeved out, as is my lower leg and my back is covered by two huge tigers. While I know that tattoos don't affect my ability to be a lawyer, and people are gradually more and more accepting of tattoos as a means of expression etc, I wouldn't choose to disclose to my firm that I'm interested in/ collect tattoos (and would never have my hands/ neck etc inked) because, unfortunately, there are definite pre-conceived notions about tattoos.
To that end, I would probably just mention "dancing" without specifying that it is particularly pole dancing- I think this would tend to strike a balance between being authentic but also mitigating the risk of someone with preconceived notions perhaps judging you in a different light for that.
Others may have differing views on this- I would caveat my response by saying that I don't think anyone should ever need to be embarrassed or anxious about disclosing a hobby or interest and it's a real shame that we have to have discussions like this. Alas, though, we do and personally I would always err on the side of caution/ pragmatism in spite of the fact that it shouldn't have to be a consideration.
Hopefully one day we'll not let such silly little things dictate how we assess somebody's suitability for a role...