The Shopify Custom App connection method allows you to retrieve inventory from other Shopify stores without the need to install the Stock Sync app on that store.
However, the other Shopify store has to create a private app. Steps:
1. Navigate to Shopify Admin > Settings > Apps and Sales Channels.
2. Click on Develop apps.
the Create an app
4. Once you click on Create an App, it will pop up. You need to enter the App name and App developer email. Then, click on the Create app.
5. Then, it will direct you to this page. You must select the tab API credentials to get the API key and Password.
6. To access the tokens, click the Configure Admin API scopes.
7. It will direct you to this page. You need to find the Products and check the box of read_products. Once selected, click Save and Install app.
8. After installing the app, you can see the token, API key, and secret key.
Shopify API password starts with shpat_
If you need to get inventory from Store A to Store B, please create a custom app and install Stock Sync on Store B.
Paste the API key and Password in respective fields and also the Shopify domain storeA.myshopify.com gets from the Store.