I have done a lot of text that was galvanized, powdercoated, and painted.
You would need to design the text so that the cuts are not a single pass with the waterjet, but are actually typestyles with ample room. The galavnizing will cover about like dipping in honey- small holes, and narrow cut lines, will fill in. You usually have to rethread holes after galvanizing, and, often, file or grind out slots and corners that have filled in too much.
I have also engraved text with a ball mill, then galvanized, and that works pretty well, assuming your characters are 3/4" or 1" tall (20- 25mm in height, and perhaps 3mm deep).
I have also hot stamped text in steel plate, then galvanized, which works pretty well. As does cutting out positive letters, and riveting or bolting them on after they have also been galvanized.