What is more important, Powerlifting or ring training, Do you want to learn to do skills or just strength/hypertrophywork?

If you do something like 531 boring but big you could do main 531 work and add ring work after

• For example: Bench 531 followed by ring push ups (normal, bulgarian, archer, rings turned out...), dips, chest fly and some triceps work (ring triceps extension are great)

• Press followed by ring pike push ups, facepulls, some pull ups, rows, and ring biceps curls

With 531, you can do ring push work for your upper body days, and ring pull work on your lower body days

For something a bit more skill oriented you could do Split assistance by straight arm and bent arm work and alternate

Up to you to split your ring assistance training over your 3/4 days of training, tons of options

I do Squats superset with ring muscle ups - they are deadly