As of 02-03-2021, Visual Studio Code's Find All References feature doesn't work between apps and libs in Nrwl Nx workspaces. This Node CLI utility temporarily and non-destructively applies the workaround from that GitHub issue to your Nx workspace.
Run farp in a Nrwl Nx workspace to apply the patch.
Run unfarp to remove the patch by restoring the original tsconfig files.
Unfortunately, your code will not compile while the workaround is in place.
Unit tests do seem to work, though.