Bleach dish cloths in a plastic bowl or steel bowl?
If I were to soak dishcloths in cool water, should I soak them in a steel bowl, a plastic bowl or in a clay bowl?
Stainless steel yeap.
Glass bowls is a great idea.
Once I start, I can to use the bowls for only bleaching dishcloths.
Bleaches are mostly fairly strong oxidizers. Of the three choices, given, I'd probably use a glazed ceramic bowl if the same bowl will be used repeatedly for many years (actually, I'd use a glass bowl). But given dilute solutions and cool temperatures, any of these should be fine in the short term (assuming you're talking stainless steel, not, say, carbon steel).