Zoho One Subscriber - Successful migration from Google to Zoho Mail & TeamInbox

Zoho One Subscriber - Successful migration from Google to Zoho Mail & TeamInbox

Hi,

We are a Zoho One subscriber for past many years. We are also a Google Workspace Legacy User. 
We are about to make the transition from Google Mail / Drive to Zoho Mail, TeamInbox & Workdrive.

Is there anyone who has done it successfully or can share experiences on do's & don'ts would be helpful.

Apart from standard employee email accounts, in our Gmail, we also have
1. function email accounts (hr@ , commercials@ , accounts@ ,)
2. project email accounts (xyzproject@ , abcproject@ ,)
3. Old Employee accounts (old-employees-sales@ ,old-employees-delivery@) Employees who left, their emails were backed up in these accounts for future ref).

We have tonnes of Google Drive data, alongwith Gsheets, Gdocs & Gslides (some of them are over 20MB files when converted to Microsoft formats).

Any ideas and suggestions?