Mens' leotards are fairly readily available, and, yes, their crotches are designed for mens' bodies, though the chest is sometimes questionable.
M. Stevens sizes are a little odd - Small is VERY small, the seat automatically becoming a thong by itself, but after a few washings fits well (on me anyway)at the expense of new Millskin's superior but slightly-stiff feel and fit. Meanwhile, a new well-fitting medium becomes relatively nonsupportive after a few washings. I haven't tried a Mirella men's leotard, but their Tactel blend makes fabulous tights, so by extension their mens' leotards should be great. Capezio and Danskin currently make no menswear (besides belts and shoes).Bal-togs' menswear is very good.
Online purchasing, try NY Dancewear, Action dancewear, and Pumpers, though they tend to be expensive. Discount Dancewear has good prices but they don't have as much menswear as they used to. (Not their fault: The last couple of pair of tights I've bought through them all had holes in their factory seamwork.) River's Edge Dancewear has good prices and a great selection (including the ONLY mens' long-sleeve leotard I know of), but can be slow. Tutu.com has a very fair collection of menswear and their delivery is fast.
Please note that Mirella's mens' leotard features cap sleeves and a thong. Theoretically, this would have just the right amount of material for rolling down to, then with, your tights, eliminating the need for a belt while allowing barechested comfort... If your studio starts off cold but ends up very warm from dancers' body heat, such a "modular" approach to mens' dancewear may be ideal.
Dazzle 'em!
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