Offset any closed path outwards or inward by entering a + or - value in mm, fx offset path by 0.8 mm outward (+).
As it is now, the only possible workaround is to add a stroke (twice the size of the intended offset size with value converted to points as strokes work in points only) and then outline the stroke and delete the excess stroke.
That workaround is a bit annoying…
Hey @Christina, thanks for the suggestion.
Introducing an offset path feature is certainly on our radar so please stay tuned for future announcements!
Hey @Christina,
Great news! Offset Path is now available in our latest version 4.8.2 
Please check out this latest update to explore this exciting new feature as well as Default Colour Palettes, improved Auto Trace and more!
You can learn more about how to use Offset Path here
Cheers,
Helen
Hi there,
Why is “Offset path”-unit in “pt” only? The distance between the offset paths are not strokes but physical space on a design. Please make it possible to permanently choose between “pt” and “mm” for “Offset path” in “Preferences”.
Hopeful regards,
Christina
Hello 
,
I was also wondering if it is a bug or if there is a reason for only having the opportunity to offset in pt ? Would enhance the workflow a lot, to be honest and make offsetting pathes way more precise than with all the workarounds. Unfortunately if my design needs to be precise I am jumping to another Programm at the moment.
Thanks in advance
Philipp