Hi @Anuj31005349h74z ,
If you are using App Builder, why not try them in batches. Adobe I/O Runtime leverages the container’s auto-scaling capabilities. A very good read would be https://blog.developer.adobe.com/adobe-app-builder-the-power-of-scaling-at-your-fingertips-8ae1149b7...
Else of course you can build a custom solution which would take significant time & effort -
1. Read the PIM daily by running a scheduler (you can adjust the frequency)
2. Save the data as Content Fragments
3. A sling job can then fire a query for new/changed content fragments to list assets related to a particular product ID, say lists all assets for an eanCodes.
4. Then just map the data onto the asset metadata.
Hope it helps.