You can translate openblok by creating translation files in GNU gettext format.
# create/update base files
cd locale/
# find relevant files (in this case using ripgrep) and save them into locale/POTFILES.in
rg -l 'tr\("\w+' ../src > POTFILES.in
# scan all relevant files for usages of tr() and extract strings
xgettext --keyword=tr --language=C --add-comments --sort-output -o main.pot --files-from=POTFILES.in
# example for german (de) locale
# option1: if new language
msginit --input=main.pot --locale=de --output=de/main.po
# option 2: updating existing translations
msgmerge --update de/main.po main.pot
# create translation file for locale
msgfmt --output-file=de/LC_MESSAGES/main.mo de/main.po