From my experience Workbench does not currently support it (symbol navigation does not work as well as debugging etc).
If the answer is "no" — does anyone has the experience with some IDE and "new package format"?
I've checked Idea plugin (which I actually have paid version), but it seem to have the same problem: symbol navigation does not work across files.
VSCode has very limited support for Wolfram Language (and getting language server to run stably seems next to impossible).
Thanks in advance.