It should take about 5 minutes to make the adjustments. It's really not a big thing. I shoot self bows, straight limbed longbows, hybrids and recurves. High wrist, low wrist. No problem going from one to the other.
I disagree with the tight grip advice. The tighter one grips the bow, the more the excess energy that is transferred from the limbs to the riser to the bow hand will be felt, resulting in more felt hand shock. Heavy recurve risers ameliorate this considerably by absorbing much of this energy. Small, light longbow risers do not. A firm, but not tight grip is much better IMO. Good luck.