Looking for more complete and ready solution.
[SOLVED]
Dependencies:
Cyrillic fonts from https://www.gnu.org/software/freefont/sources/slackpkg install groff perl woff2
slackyd -g fontforge
installpkg /var/slackyd/fontforge*.txz
Font installation script from groff mom sitewget -P fonts --no-check-certificate https://mirrors.ctan.org/install/fonts/tempora.tds.zip
wget -P fonts https://www.schaffter.ca/mom/bin/install-font.sh
cd fonts
unzip tempora.tds.zip -d tempora
cp install-font.sh tempora/fonts/type1/public/tempora/
cd tempora/fonts/type1/public/tempora/
To use font family at the begining of the document must be:sudo sh install-font.sh -s -F Tempora -f +R Teinstmpora-Regular.pfb
-s if your distribution has /usr/share/groff otherwise -l if /usr/local/share/groff
repeat similar for bold italic bolditalic +B/+I/+BI
Groff can use only pfb fonts but install-font.sh can convert and install other like otf ttf..ds FAM Tempora
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Groff module that supports UTF-8 cyrillic convertion to pdf with font Tempora.
https://filebin.net/hsfd6njhac3ciebq