I bought a cheap ultrasound cleaner, was about $50 bucks. Something like https://www.amazon.com/Magnasonic-Professional-Ultrasonic-Eyeglasses-MGUC500/dp/B007Q2M17K
Then let the keycaps dry on a towel, and after some hours individually wipe them dry.
Mandatory, guide on how to buy a mountainbike:
https://youtu.be/yotOZVELSMc?si=gfwq63bEiIVxUggr