You can change it, but you need to edit the source code of one of the Ace libraries Bartender uses:
Originally Posted by futcher
(I'm assuming 2 things here, That you use a PC and that you use Bartender - Dominoes might be different, I don't use it and don't really wanna spend even more time dissecting that addon to figure out how it abbreviates the key binds.)
1. Locate the Bartender4 folder within /World of Warcraft/Interface/Addons/
2. Within the Bartended4 folder, open /libs/LibKeyBound-1.0/
3. Identify the "Locale-" file which corresponds to the locale of your client (Locale-enUS for English clients, Locale-deDE for German etc).
4. Copy that file to your desktop as a backup, just in case you make a mistake or want to revert the change.
5. Open that file in Notepad.
6. Scroll down until you see the line '-- This is the short display version you see on the Button"
7. The following 4 lines show modifier keys and what the library will abbreviate them to. Change them to read how you wish, to have them shown as they are in the default UI, change them to read like this:
8. Save the file, load WoW. The binding text should now read how you want it to. You'll need to redo this change every time you download a new version of bartender as the file we changed will be overwritten.
["Alt"] = "a-",
["Ctrl"] = "c-",
["Shift"] = "s-",
If you need any clarification, PM me. I'll probably forget to check this thread again.