How to create a cell of IDs of related products (in the row of an original product)?

Hi All,

I would like to create a product feed for my company, where each row represents a product. Sometimes a product has some additional feature, which acts as a separate new product (in a new row).

Example:

Main product -> ID:1
Main product with feature #1 -> ID: 1.1
Main product with feature #2 -> ID: 1.2
Main product with feature #3 -> ID: 1.3

After all this, in a certain product row I would like to display the other 3 products as "related items" in a separate column. So If the visitor is on the product page of the "Main product" he/she should see Main product with feature #1, Main product with feature #2 and Main product with feature #3 as related products.
Therefore I would like to display always the other productsī product IDs in a single cell for a certain product.

Example:
In the row of my Main product (ID: 1) I would like to see a column (related products) with "1.1, 1.2, 1.3".

OR

In the row of my Main product with feature #1 (ID: 1.1) I would like to see a column (related products) with "1, 1.2, 1.3".


I hope this makes sense. Thank you very much for your help in advance!