Not recommended. Even if you avoid the very real issue that
@Mesatchornug notes by racking the slide to strip the top round from a magazine and then toping off the magazine, there are other problems.
Putting it into that state (Condition 2) has some risks. Hammer slips from grasp and drops while trigger is pulled to 'set it up'. Yes, there are safe(r) methods (other thumb in front of hammer for one) to lower the hammer on a firearm without a decocker but the concern is doing this repeatedly leads to errors of familiarity. And, there are problems with cock on draw. First, it's a much more fine motor skill than dropping the safety which can be part of your first draw step of establishing of grip. 'Training' the cocking of hammer is where the accidents will be most likely to happen because would have to be part of your draw drills and see preceding where the risk of an ND increases. (Yes, the half cock notch helps but I am not sure a 938 even has one, nor should it be relied on if it does) Third, a slip up in a stress situation massively increases the risk of premature unaimed discharge during an actual draw for all of the preceding reasons. Don't.