Open Greek fonts
The MgOpen collection includes typefaces that contain glyphs for viewing texts in Greek and English; the company MAGENTA LTD. offered these so as to be made available as free software. The collection presently consists of four typefaces (named Canonica, Cosmetica, Modata and Moderna) while there is also a fifth one (by the name Apolyta) which should be made available as soon as it is completed with latin characters, which are currently missing.
The fonts are available for download and installation through their web site as well as through a package (by the name ttf-mgopen) in the Debian GNU/Linux distribution.
For mgopen please see this web page: https://packages.debian.org/sid/fonts/fonts-mgopen.
For additional Greek open fonts see https://github.com/eellak/gsoc17-Eczar, https://github.com/eellak/gsoc2018-arimamadurai and https://github.com/eellak/gsoc2018-cantarell from https://ellak.gr/wiki/index.php?title=Google_Summer_of_Code.