I haven't been playing Morrowind for a while. But I would like to come back to it and try a little powergame experiment. But I want to know if there are any mods that can let me select multiple instances of training from a trainer at one time. So, for example, I could train my marksman skill 10 times for a big lump sum of cash, and 20 hours would pass. I just get tired of clicking through every skill-up.

Since there is no scripting function or dialog option to modify this, even using MWSE, it is, unfortunately not possible without rewriting the .exe.