What you really want to do is "repeatedly" train in Bodyweight / Calisthenics/ Gymnastics/ Acrobatic oriented muscle chain & neural pathways, across varied planes & directions of motion; especially those of disadvantaged leverage.
Now, rock climbers may have "higher endurance" due to longer climbs, but pound for pound the disadvantaged positions some of these folks bodies can achieve would leave a climber flabbergasted. That is strength in "directions" that no climber or body builder would have ever bothered, which they have to have trained to perfection.
One of the places I got into that initially was a forum called BodyWeightCulture (.net).
That eventually led me to an article on Dragon Door around Gymnastic Strength training by Coach Christopher Sommer who sometime around/ after that started "Gymnastic Bodies" website, forum - which led to a Book and Online training programs.
Gymnasts undergo some of the highest loads & variations of loads in different directions than any other sport, so their training centers hugely around not just muscle strength, but tendon & soft tissue with mobility and strength in all directions of disadvantaged leverage.
So, being able to "condition" and "strengthen" the entire muscle/ body chain and control its "coordinated" movement & proprioception is going to be uniquely beneficial.
There are a few other programs/ books around this from other sources so do look it up, but largely this was usually knowledge only known to people in the Gymnastics arena that is now out.
A picture worth thousand words; You and I wont reach this anytime soon, but the direction/ pathway is as good as it gets for Strength to Weight ratio.
The books & training programs are copyrighted so I cannot share the content but if you are so inclined you can find the Table of Contents and some previews & freebies online that depict/ show/ indicate the direction of these & Articles that give you a glimpse into the types of exercises.
Rock Climbers using / training in similar ways:
Case Study: How an Accomplished Climber Used Gymnastic Rings for Better Performance - https://gmb.io/climber-sami/
Cautionary Note: Some reference samples of starting points/ mid points & where it goes.
Some of these are advanced moves so there are progressions & conditioning to get there. Since the advent of GB/ GST lot of tutorials (good & bad) have popped up.
Please do your homework before you try them as they can screw up your joints/ tendons if done wrong or done before your body is that level.
To whet your appetite (free content from their FB/ Youtube channels):
Great Overview / Fundamental Article by Steven Low (former GB member):
His 2nd Book
https://www.amazon.com/Overcoming-Gravity-Systematic-Gymnastics-Bodyweight/dp/0990873854/ - See Table of Contents
Where it all Started: GB Forums
Multi Plane Pulling (a term never heard or seen by me elsewhere - Google it)
Yewki and it combines a pullup, a row and a front lever together
Front Lever Progressions:
360 Pulls - A Multi-Plane Pulling Exercise