Both the .fh10 and .fh8 files originate from Adobe FreeHand MX program, albeit from different versions of the program. It may be possible that version 10 allowed users to save to the format used in previous version, unfortunately we weren't able to determine whenever this was actually possible. In any case, using FreeHand seems like only viable option for fh10 to fh8 conversion.
Updated: February 2, 2021
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