This skill list is of course probably idealistic as you have no real control over the skills that volunteers will bring to your project.
Nice to have:
Many people say they are proficient in multiple languages. Some people are, most people aren’t. The problem with people with multi-language skills is that they often do not have access to a deep understanding of either language. And a deep understanding is what you need if you want to find words that can be reused in a different way in a computer translation. So treat the polyglot with caution until proved otherwise.
This may seem redundant but a person who is passionate about their language is much less likely to say well there isn’t a word for “Proxy Server” and is more likely to understand the need for a good and extensive translation.
Someone who has no computer experience will not have the best understanding of words used differently in the computer world – words such as ‘execute’ and ‘run’. But a BSc is also not needed. You need someone who can comfortably use a computer they can always lookup difficult words in online computer dictionaries.
This is a nice skill to have especially when defining terminology that requires a deep understanding of language, etimology and computer usage and definitions.