Shopify 'Sales Channel App' expert for App approval

Description

We seek a knowledgeable and experienced Shopify Sales Channel App expert to guide us through creating a custom Sales Channel App for an online Marketplace with the bare minimum features required as per Shopify guidelines.
The custom app needs to allow Shopify sellers to install the Sales Channel App, register in the Marketplace and send their products to the Marketplace. The seller shall update further order processing, product updates, and shipping from the Shopify seller account.  
We must define the minimum viable features that Shopify requires to approve the Sales Channel App.
The consultant shall provide suggestions and guidance on defining the bare minimum features as well as ensuring that the app meets all of Shopify's needs for approval.