Figurativelanguage refers to using figures of speech in order to be more effective, persuasive or descriptive. It usually relies on using words in ways that differ from their literal accepted meanings. Therefore, this allows the author to use words in an unconventional way. In this case, the phrase does not mean that the warriors literally turned into hornets. Instead, it describes te warriors as being as violent, relentless and decisive as hornets.
The quote means that to be a part of your community, you have to be like everyone else. If you are not like everyone else than the other people in the community will just ignore you or treat you as an outsider.
