Voyager recently added user tags (allows you to label other users) but the app also doesn't appear to use the display name option available in Lemmy (or at least no one has it enabled from the screenshots I've seen posted), so it just shows the username you use to log in, which doesn't have special characters.
My display name is my username, but spelled using emojis in case you don't see it that way, either.
Oh, I see. Voyager doesn't show that because display names are confusing for mentions, can be used to impersonate, and distracting. It might be an option to enable in the future, off by default.
I read, write, cook, paint, swim, travel, and hike, and last gardening. I should be rolling in it. But my wife finds me sexy so I got that going for me.