A creature that has telepathy can communicate mentally with any creature that has a language, even if they don’t share the language. The other creature must be within line of effect and within a specified range. Telepathy allows for two-way communication. (RC 316)
There is no restriction on the keywords associated with the character, if they have a language, are in range, and in line of effect, you can get in their heads.
Worth noting that the Revenant is not specifically immune to telepathy so there again, no issues communicating silently.