For anyone still wondering how to do this; I found a solution that works pretty well.

Just as the topic starter I have products that have many variations, and needed a solution to automatically generate reordering rules. 

What I did is create an Automatic Rule when a product is created. As Model choose product, on creation Action To Do: create a new record for the Target Model "Minimum Inventory Rule".

Then you can adapt the fields as you want. For me it was creating the Min/Max quantity rule to 0. Don't forget to also add the product id as a field, you can do this by choosing Product (stock.warehouse.orderpoint) as field and Python Expression as type with value "record.id".

Hope this helps!

 I have similar situation , i am making  a small code to make it automatically, will post  it here once ready , right now  I am using ,  import the reordering rules, you can do it directily in reordering rules form .
 

Hello Chris,

If you don't want to use reordering rules, then you can configure all your products as make to order which will create the procurement that will have demanded quantity.

I also found this function annoying -- You create a product, then have to leave the screen and goto "Reordering Rule".  It will be nice that "Reordering rule" is incorporated into Warehouse > Products, so this can be done as part of creating a new item (like adding other product details).