TruFont the font-editing application written with Python3, ufoLib, defcon and PyQt5 now has support for pasting SVG images as glyphs. It now also support drag and dropping SVG files. 
For my font design workflow I mainly use Inkscape to desgin master drawings and then use fonteditor for further editing. I am migrating the fonts we maintained to Trufont from Fontforge(It is no longer developed). But, not having SVG support with Trufont was a blocker for me. So today I filed two patches and got merged to Trufont master.
There are still some known issues. Mainly the pasted svg is vertically flipped. The editor can flip it again. But the original issue need investigation.