How to Revert a WordPress Multisite(subdomain) to a Single-Site

Hi, I have Multiple Site(main domain + 40 subdomains) in Network now i have to
Separate this subdomains and need wordpress dashboard for each subdomain and main domain because getting few problems when managing all site from one dashboard. I know how to revert this but this is long process like export data, then create separate installation, then import data etc.

But I want to know that there is any another simple solution Revert a WordPress Multisite(subdomain) to a Single-Sites because we have 40 sites not 3 or 5.

Thanks