I updated PS on iPad today (Ver 1.2.0 Feb. 19, 2020) hoping this might be fixed in the new release but no. If you create a text box in Photoshop, then click the microphone button on the keyboard and attempt to dictate words, you get the first 2 letters of your word, then a long space, then nothing further. Dictation simply doesn't work. Confirmed by other users on your forum. I've also noticed it's not possible to copy words from say Notes and then go into PS and paste. PS will only copy/paste info from within PS. Not expected behavior in either case.