unfortunately, the current release of Freestyle doesn't have an option selecting Inches and Fractions for Units. Here is the link to Freestyle Wish List, where Freestyle users suggest a feature that they would like to see implemented in Freestyle as well as vote for other users suggestions, thus letting Freestyle development team prioritize user requests.
Please log your suggestion regarding implementing an option selecting Inches and Fractions for Units in Freestyle. Hopefully other Freestyle users can find your request useful and vote for it.
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