@Obed Murillo are you familiar with this topic?

1. Can the Merchant Center be customized for individual sellers to manage their products and orders?

    

   Yes, with a custom application, you can create a management CRUD app for sellers. This app can have appropriate permissions so that the sellers see only the app and not the full MC.

2. Is it possible to brand the admin panel with the seller’s logo, color scheme, and other brand elements?

    

   Yes, you can fully control the look and feel of the custom application. However, since it lives inside the Merchant Center, the commercetools branding will still be visible. Once sellers click on the custom app, it can display its custom branding and colors.

I hope it helps.

You really can’t change the branding. It will always have the CT logo and colors. Technically, it could be done with JavaScript, but it would be a hack and prone to issues. The login and entry page can not be customized at all.

You will also be tied into the Merchant Center user management solution which doesn’t give the best options for permissions, sign-up, etc.

It would be better to create a new portal designed for the sellers.

I agree with @James Luterek , I don’t think your case suites in the purpose of the Merchant center. Building a multi-tenant app will give you also more flexibility and perhaps the ability to have other functionalities (e.g. notifications, seller dashboards, user support, etc..)