This is what worked for me:
npm pack + package.json
STEP 1: In module project, execute npm pack:
This will build a <package-name>-<version>.tar.gz file.
STEP 2: Move the file to the consumer project
Ideally you can put all such files in a tmp folder in your consumer-project root:
STEP 3: Refer it in your package.json:
STEP 4: Install the packages:
npm install or npm i or yarn
Now, your package would be available in your consumer-project's node_modules folder.
Hope it helps!!