I have a site that needs to post a bunch of Chat Dialogs. They want the request to show up in a specific color on the right and the results on the left.

They specifically want to avoid the Block Editor because they want all of the themes to look the same.

Is there any way to add a ribbon or toolbar to the standard editor that would allow someone to press a button to assign selected text a custom style? Even if this had to be a custom template that used shortcodes to assign custom styles, I need a ribbon or toolbar to insert the shortcodes for them.

Does anyone have any suggestions for how to manage this? Thanks in advance.