2. Change the first subtitle first.
3. Then open the Character Styles panel.
4. Then click the Create New Character Style icon.
5. Get the character style 1.
6. Select the check icon at the bottom of the Character Styles panel and click it to save the character style modified in the first step.
7. Select all the text layers to be changed to the same character style, select the character style 1, and then click the rotation arrow below. That is, you can modify character styles in batches.