Does anyone have a difference in their ability to crimp depending on which hand.
Seems pretty normal to me.
I'm recently recovered from a pulley tweak so easing back into crimping. Because I've been dragging 99% with my right hand for a few months now so it doesn't want to crimp.
Like you say it's an essential grip though so in the last 2 weeks I've been hitting the campus board to specifically tackle this. I do deadhangs off the half crimp to get comfortable with it and build strength, and then move off it, on mid and small rungs.
It seems to work. The first week I had to really concentrate on maintaining the half crimp position and could barely hang more than a few seconds off the small rung but this week a full set of repeaters is fine and moving off feels much more natural.
I have no problem crimping on my left hand but with my right hand I try to crimp but often my hand decides as I'm moving on the hold to stop crimping and start dragging.
Although I think I'm stronger at open handing than crimping,
It seems to be a synergistic thing to me- if you're weak at half crimp and much stronger at dragging your hand will move to drag when the going gets tough.
So build up strength on the half crimp to be more in line with your open hand, and it will also become more natural feeling and your hand will decide it's an alright grip to use when you need it.