Reply To: bold modified single letters as word parts
A modified letter is still a letter, but with a hyphen before or after (or both) it would be fine to italicize just the letter, or the letter-hyphen combination (as a word).
In a foreign language textbook where this type of thing will come up often, I think it makes the most sense to use the italicized word indicator and include the hyphen(s) in the italics. It's easier for you as a transcriber, and it's clear and consistent for the reader to have the italics come first in a symbols-sequence, to signal the language change.
So, in this case, "e-" "-v-" and "-a" would be brailled as: [italicized word indicator][e][-] / [italicized word indicator][-][v][-] / [italicized word indicator][-][a]