Hello. Of course, you can.
1. For the start u need to set up aion's localization to russian.
2. After applying new localization, you must copy the Sounds folder in the following path - ..\Aion\L10N\rus(or eng)\Sounds.
3. After copying, return the localization to english.
4. Replace copied(point 2) Sounds (from ru localiz) to Sounds (eng localiz)
Gl.