Not the same especially with grip style but you can go a long way by strengthening your back. I'm talking of horizontal and vertical pulls (heavy rows, pullups, lat pulldowns, deadlifts to an extent).

In my unscientific observation, a lot of people have very weak posterior chains. My wrist pain has always (so far) been the result of a knot in my upper back or a weakness there.

Don't forget to foam roll, stretch and perhaps add in some periodic deep tissue massage to keep things from getting too tight cos that also brings problems

Search for climbing fingerboard or hangboard.

Good for fixing or hang above a door way.

You don't need to actively climb on these, hanging from the holds will do the trick and reduce the possibility of dynamic loads.

I used this as well. Same issue as bouldering. It tends to stress the joints too much.

For whatever reason, regular climbing is better. Probably because there is more 'levels' and thus less immediate stress. You can't really climb to the top of an indoor route until you can learn and get the strength to do it.

With fingerboards you try to see how much you can tolerate and tend to over do it. It also is more of a static movement. Grab and hold. Where top rope climbing is more dynamic... you're constantly moving up the wall in various poses.