Is there a Linux software to spell check .po files?
Solution 1:
I've just pushed a po file spell checker to github: https://github.com/holygeek/pospelchek
The behavior imitates aspell wherein it shows you the mispelled word and suggests corrections.
Run it like this:
$ pospelchek -l de_DE lordsawar-0.2.0-pre4.de.po
or to get the man page:
$ pospelchek -h
Solution 2:
You could try this online tool: poeditor.com, it doesn't have an actual spell check option, but you can have a translator do that for you via the platform as a contributor to your project, or you could try to compare your translation to an automatic one that the program can generate.