Will pop3 retieve external email through a client?

Will pop3 retieve external email through a client?

When I use Zoho mail through a Windows client (Pop3) will I be able to read my external email accounts that I have connected to Zoho through POP?

I know the IMAP protocol cannot do this. Just wondering about POP.

I want to use Zoho in my client to retrieve mail from gmail over VPN. Google hates VPN and will not allow client access while I am using it.

Thanks a lot.