The best option is probably to use the Inkscape extension developed by Anatoly Besplemennov - the App doesn’t have an import feature. Inkscape supports quite a few different drawing formats and can output directly to Line-us through the extension which you’ll need to install after installing Inkscape. There are instruction on how to do this on the Inkscape website, but here’s a quick summary:
Extension
To install a new extension, download and unpack the archive file. Copy the files into the directory listed at Edit > Preferences > System: User extensions. After a restart of Inkscape, the new extension will be available.
Hopefully that helps, but if you have any questions let me know.