I'm using inkscape from experimental, I don't known if the problem
is related on some not enough updated dependency package (pango etc)
In the font selector sans-serif has a warning, and the hover
says the font is not on system
I've tried with different fonts registering as sans-serif
(checked with fc-match)
I've tried to debug the problem, but I was unable to track where it
originates.
Version 1.2 does not exposes the problem and I have no other fonts problems.
BTW inkscape fundation will release 1.3.1 in the near future