ABGRSerif is a BGR serif font based on the PTSerifBGR web fonts found on the Official spelling dictionary of the Bulgarian language website (https://beron.mon.bg/). Those fonts were modified to make modern Bulgarian letter forms the default Cyrillic characters, and the old forms were moved to Stylistic Set 01 (ss01).
Those fonts were just the four RIBBI fonts which I have converted into variable fonts, and added Medium and SemiBold weights.
Since they were web fonts the character set is rather limited.
This project was sort of a test run for converting the full GF fonts into variable fonts.
The BGR characters in these fonts will be added as a localization (loclBGR) in the full versions.

Formats included: OpenType-PS and OpenType-TT, variable and static, .otf and .ttf files. All those formats are included in the release ZIP file.

Download ZIP here:
https://github.com/kenmcd/ABGRSerif-Font/tree/master/releases
GitHub kept rejecting the ZIP upload on the Release page (with no explanation), so I just uploaded it to a folder.