How can I achieve better isolation with Windows 10 multiboot?

My Setup

My setup looks like this:

1. Drive 1: Windows 10 System Drive - Joined to company domain.
2. Drive 2: Windows 10 System Drive - Joined to personal domain.
3. Drive 3: Fixed drive - additional storage for Drive 2.

This gives me multiboot and allows me to share a hardware while keeping my work licenses and files separated from my personal.

Problem

Ive noticed there is still some cross contamination between the 2 OS's.

• In the file explorer, I can see and view the contents of all drives, including the additional system drive.
• Somehow, OS 1 detects my Microsoft account used on OS 2. It offers to let me log into my Microsoft account used in OS 2 in desktop apps (ex: OneDrive, SharePoint Designer).

Proposed Solution

I believe I can discoect Drive 1 and use BitLocker to encrypt Drive 2 and 3. One risk here is that once encrypted, OS 1 will still have some knowledge or hooks to OS 2 and once encrypted, will make OS 1 angry. I leaed this the hard way on a previous attempt when encrypting drive 3 (which is where my OneDrive folder lived) with a password (not a TPM module) and didn't give the system drive on drive 2 a way to unlock it automatically.

So my question is: is this a safe approach? Is there a better way? Will this achieve the isolation I am looking for?