It's possible you already have the English files but just need to change a variable in a config file.
Go to the data folder in the Mass Effect 2 installation folder. If you have a retail copy, it's Program Files* - Mass Effect - Data. If you have the Origin version, it's Program Files* - Origin Games - Mass Effect 2 - Data. (*Program Files (x86) if you have a 64-bit OS.)
Open the sku ini file with a text editor. I personally prefer Notepad ++, but regular Notepad works fine as well.
Then change the language options to INT so it looks like this:
[SKU]
SKU=
VOLanguage=INT
TextLanguage=INT
If the English files are on your PC, then the game should be in English now. If not, you may have to find another way to get these English files. (I'd say by registering the game on Origin and downloading the game while your Origin client is set to English.)
That worked for me from French to English, thanks a bunch for the tip!!
