We have previously changed the saved location, you might give that a try. Go to your profile (as listed in About Opera) and edit the file Local State (yes, with a space in the name and no extension - it's just text so Notepad will work). Find where it says Country, mine reads
{"country":"us","country_from_server":"US","timestamp":"1419298826600000000"},(not certain why they removed all the line feeds since I first posted this tip)
If you want Google, you can change it to US like mine (I'd leave the timestamp alone). Be aware, Opera may change it back to your real country eventually. And of course, don't edit the file while Opera is running - at best, Opera would just overwrite it when you closed the program.
You must have one of the older versions of Opera. So far I can't even get Google recognized as an option even though it is seen as a downloaded plugin.