Here are the steps to use eSoftTools EML to PST Converter software to open

 multiple EML files in Outlook. The software supports various email clients, including 

Windows Live Mail, Office 365, PST, Thunderbird, MSG, MBOX, and others. This tool 

selectively changes files and folders and is compatible with other mail programs. Users

 can also apply their preferred email formatting options to customize the file with specific

 details such as date, time, or location.   

Know more - Import eml files into Outlook