The differences you're seeing in the menus within the QuickBooks Online mobile app for your two businesses are due to variations in subscription types and features enabled for each account, Sharprockventures.
The system adjusts its interface based on your QuickBooks plan and the features available. Each subscription unlocks different functionalities, resulting in unique menus tailored to your business needs.
Currently, the option to customize the top and bottom menus or control which icons appear on the mobile app is unavailable.
If you want a menu layout similar to one account's design, you may need to have the same subscription and feature set on both accounts.
You may also consider using the QuickBooks Online web interface to customize your menus. Refer to this article for more information: Overview of the navigation menu.
Let us know if you have more clarifications or concerns. The Community team is always available to assist.