Please, add the Xfce4-whiskermenu-plugin file to the transifex to be able to translate. Thank you.
I'm sorry, I'm confused. Are you offering to translate Whisker Menu in Galician? If that is the case, just request the language here: https://www.transifex.com/projects/p/xfce4-whiskermenu-plugin/ Unfortunately, opening a bug won't get Whisker Menu merged in with the rest of the translations. I'm not in control of Xfce's Transifex, and I don't know who is.
@Graeme if you want, you could ask Romain (Skunnyk) at #xfce-dev to enable the script[1] to also sync translations for whiskermenu. 1 - https://github.com/nschermer/txcron