There was a
thread about this on a welding forum I'm on.
Several people reported success using 12V power supplies with the positive connected to the work, and the negative connected to a conductive brush, something like
https://www.ebay.com/itm/Qty-1-Pure-...B/263542164351. For the cleaning solution, they used 1 part phosphoric acid to 3 parts water.
I've not tried it personally, as I rarely work with stainless, but the results looked impressive.