The Ag-1 flash adapter takes, obviously, AG-1 flash bulbs. There are two types, for color film and for BW film; the difference becomes apparent when you look closely at each type bulb.
The flash bulb for color is, well, blue colored. The flash bulb for bw film is clear, slightly yellow-ish actually.
Other than that, with modern filsm, the difference on the processed negative would be insignificant. At least this is what I believe, after the hundreds of bulbs fired since I have started with Minox in the early 90’s.