Will BroadBand Light for freckles affect hair follicles? Would Rogaine help with growth?

Hi there!
BBL does have the potential to damage the hair follicles in the treated area, although after 2 sessions it is unlikely to cause significant hair reduction. I do routinely advise my patients that there will be hair reduction in the treated area and I rarely treat over the beard unless the patient requests for it.
In your case, it is quite likely the hair will regrow soon although it may be a little thinner

BBL includes wavelengths between 515nm - 1200nm for pigment and 590nm - 1200nm for hair removal. Given the significant overlap, there is potential for hair reduction when treating dark spots like freckles. It is quite possible that you will regrow most of the affected hair because it takes at least 6 treatments for permanent reduction. The affected hairs can take 2-3 months to reappear at near normal levels. I always counsel male patients about this, particularly on the face when discussing treatment of the bearded areas.