Will this work as a shared library? I.e., the hundreds of megabytes will be shared between different applications? If not, maybe running on a browser is still the better option?

Yes—it’s a shared library, so apps using the same installed copy can share disk space and read-only code pages. Separate bundled copies won’t automatically do that, and each app still has its own runtime memory.

A browser is a good choice if it fits your app! Zebkit is for embedding Chromium into a native app while keeping control of the host.