Drop these TTFs into this directory before release build:

  playfair_display_regular.ttf
  playfair_display_medium.ttf
  playfair_display_semibold.ttf
  playfair_display_bold.ttf

  inter_light.ttf
  inter_regular.ttf
  inter_medium.ttf
  inter_semibold.ttf
  inter_bold.ttf

  frank_ruhl_libre_regular.ttf
  frank_ruhl_libre_medium.ttf
  frank_ruhl_libre_bold.ttf
  frank_ruhl_libre_black.ttf

All three families are SIL Open Font License (OFL). Download from fonts.google.com.
