Step 1: Creating an IMAP account:

1. Open Gmail and Goto Settings.
2. Choose Forwarding and POP/IMAP option.
3. Now see the IMAP status if not enabled, enable IMAP, and save changes.

Step 2: Configuring Mac Outlook with IMAP Account:

1. Open Outlook(in Mac) and go to Tools Tab and Select Accounts.
2. Select Email and provide your credentials.
3. Enter the IMAP server, Select an SSL connection with the SMTP server, and 465 as the port number, and select Add Account.

Step 3: Export MAC Outlook Mails to IMAP Account:

1. Start Outlook on MAC and choose the items.
2. Right Click on the folder, choose Move >> Copy to Folder.
3. Find your IMAP folder and select Copy.
4. Now update the IMAP folder with Send/Recieve button which moves your OLM Emails to IMAP format.

Step 4: Setup Windows Outlook with the IMAP Account:

1. In Control Panel, select Mail >> Email Accounts >> New.
2. Choose manually configure server settings and click Next.
3. Select the IMAP/POP setting and click on Next to proceed.
4. Give your IMAP account credentials along with incoming and outgoing server specifications and click on More Settings.
5. Enter 465 as the SMPT server port number and select the SSL connection.
6. In the Advanced Tab set 993 as the port number of the IMAP server and choose SSL.
7. At last, click on Next after a few minutes click Finish.

Hope This Helps,
Peter