Talc-free powders are made with products such as corn or tapioca starch, arrowroot or rice powder, baking soda, and kaolin or bentonite clay. These all have bigger particles than talcum powder, meaning that they are less likely to be inhaled or absorbed into the body. In addition, these products are all non-carcinogenic and are unlikely to cause any kind of allergic response.
I’m seconding the concern about starches as body powders. As a nurse, I know that starches do feed yeasts that can thrive on moist skin: along any sweaty crease like the groin, under breasts, under yer butt cheeks, etc. Hospitals once used talc, then starch-based powders, now mostly neither. I’m not being a nay-sayer. Just offering a word of caution. If ya get yeasty, maybe don’t put starch there. Can’t speak to powder combos with baking soda or whatever though.