I'm new to filter editor, and it's pretty complicated. How would you approach creating outer bevel effect on shape in Inkscape?
There are many ways to create bevels in Inkscape but it really depends on exactly what you're looking for and how much control you need. Here's a great tutorial that shows how to bevel text. You can apply the same principles to other objects too but note that the blur option specified in step 6 is available only with text.
If you want something simple you could also try filters that come with Inkscape Filters-> Bevels.