This app is pretty old, and I can't guarantee it will work on your machine.
Available for Windows desktop
If you speak (or are learning) Esperanto, you need EspType.
The Esperanto alphabet contains six accented characters, none of which appear in the default Windows fonts. EspType can download and install many fonts that support the Esperanto alphabet.
But viewing's only half of it. EspType also helps you enter those accented characters, in any program--even in filenames. With EspType running, you can continue to type "sx", "^u", "c'" or other sequences just as you do today--but EspType will insert the appropriate accented characters instead.
EspType is free.