The solution the problem is available in its statement:
File was processed with these loaders:
zuifrontend_1 | * ./node_modules/babel-loader/lib/index.js
zuifrontend_1 | You may need an additional loader to handle the result of these loaders.
Module parse failed: Unexpected token (3:9)
export * as embed from “./embed”;
The problem is not with node (12.x or whichever), because bokehjs is not a node library, but it’s web browser library. So bokehjs’ code is not run in node at any point in time, it’s just being processed by node libraries like babel-loader, which apparently doesn’t recognize this pretty new ES export star syntax. You will need to consult babel’s documentation to resolve this. However, assuming that they already added support for this syntax and released a new version of the offending libraries, then fixing this should simply require updating your development setup to the most recent version of babel’s toolchain.