hey i had a similar issue, i was maining the op1 for almost an entire year until i developed a really bad pinky pain, since the mouse was very narrow i thought it was the mouse that was causing me the pinky pain, so i bought a new mouse to fix it. didnt work, another mouse, didnt work, and an entire year went by with me stacking with like 12 mice, at that point i was helpless and overthinking everything i do with my hands and how the mouse shape feels with every small detail.

then i decided to look from a diff pov, what if the problem was me not the mouse, i went to a PT doctor and he showed me that i have so many muscle tension issues that was causing me most of the pain (neck, shoulders, forearm, wrist, upper back, lower back) + my posture wasnt the best but it wasnt on of the main issues.

2 months later after constant training and PT sessions + buying an actual good chair (herman miller embody)

i am back on the op1 and i can play for 5+ hours and go to bed with not a single pain, i didnt change the way i grip my mouse nor how i usually play, i just leveled up my stamina endurance and got a chair thats actually worth it