For spoken Arabic, a decent placeholder is either MSA (standard Arabic) or a generally understood dialect (Egyptian or Levantine).
The latter is what a lot of the recent Arabic game dubs have been doing (e.g., Ubisoft). Another example: Pixar and Disney use Egyptian Arabic for their dubs.
Edit: Oh, and for written Arabic, you should almost always be using MSA. That is, you shouldn’t worry about the dialect of your target audience.
For spoken Arabic, a decent placeholder is either MSA (standard Arabic) or a generally understood dialect (Egyptian or Levantine).
The latter is what a lot of the recent Arabic game dubs have been doing (e.g., Ubisoft). Another example: Pixar and Disney use Egyptian Arabic for their dubs.
Edit: Oh, and for written Arabic, you should almost always be using MSA. That is, you shouldn’t worry about the dialect of your target audience.