Coping with not speaking local language, as an academic?
Learning a language is a lot of work, particularly if it is not that similar to languages you already know.  So it's not an endeavour to undertake just because you might get a job somewhere later.  You need real motivation to learn a language properly.  The main reasons I see for an academic to learn a language properly are: because you enjoy learning languages, because you plan to spend a lot of time in a place it will be useful, or because you need it for your academic work.

If you are serious, in academia there are resources that may be easily accessible to you.  The main ones are:


take/audit language classes at your university before going there
take language classes for foreigners at your destination university


Universities get a lot of foreign visitors, and depending on the university, they may have other support besides their own language classes.

I did a 1-year postdoc in Japan, and one piece of advice I got from someone who was doing a postdoc there before me was start learning Japanese as soon as possible.  So I studied Japanese for about a year beforehand both by taking university classes in the US, as well as some extra studying on my own.  I also took lessons in Japan, as well as studied on my own.  While my Japanese is still far from a native level, after a couple months in Japan, I could handle most non-technical communications on my own in Japanese.  

I do want to stress this requires real effort on your part, and it's hard if you don't really enjoy it or aren't serious about it.  I met several foreigners there who just attempted to learn Japanese by osmosis and maybe some small efforts on their own, and even if they had been their many years, they couldn't have a real conversation in Japanese.