Most of our designers' files are 85% consisted of instances from shared Sketch library. Although I managed to recreate and improve that library relatively quickly in Figma, all instances in imported designers' files will require manual re-connection to the Figma components. How did you handle that? What is your process?
I was dealing with something similar a year ago. At first, I imported the Sketch library into Figma, made few tweaks here and there, but while it worked quite well it didn't really fit Figma workflow. The different ways how they handle symbols/components override lead me to redo the whole thing from scratch.
It might look like it will be a pain to do, but since Figma gives you a bit more freedom with components, the resulting library will be far smaller. So it kind of compensates. I wrote about it in some detail over here.
I tried importing it into Figma but found that the work file became super slow. First I thought that it was Figma that was slow but I kept hearing how fast Figma was compared to Sketch so I decided to rebuild it from scratch in Figma instead. It made a huge difference in performance for some reason. Also, you probably want to restructure your components because they work differently in Figma compared to Sketch. Figma's components are more flexible and usually require fewer components to get the job done.