For localizing Info.plist values, you will need to create a separate strings file called InfoPlist.strings under your language-specific project directory, such as en.lproj, etc, and put the key and the translated value there, for example:
Pushwoosh_APPID = "2B46A-F82CC";
Take a look at the reference of Information Property List Key:
... you store the values for a particular localization in a strings file with the name InfoPlist.strings. You place this file in the same language-specific project directory that you use to store other resources for the same localization. The contents of the InfoPlist.strings file are the individual keys you want localized and the appropriately translated value. The routines that look up key values in the Info.plist file take the user’s language preferences into account and return the localized version of the key (from the appropriate InfoPlist.strings file) when one exists. If a localized version of a key does not exist, the routines return the value stored in the Info.plist file.