To keep the original sender and date details, convert the MSG files with their mail headers intact. These details are not taken from the file name. They are stored inside the message data, so copy pasting, renaming .msg to .eml or random export methods can create wrong dates, blank sender fields, or missing recipients.
For multiple MSG emails, first keep the original folder untouched. Then convert a small batch and check the EML output in your target email client. Look at From, To, Subject, Date, body text and attachments before moving the full folder.
For this kind of header safe MSG export, Datavare MSG to EML Converter gives a cleaner workflow for users who need bulk EML files without disturbing sender identity, sent date, formatting and attachments. Try the free demo on a few MSG emails first, then process the full folder after checking the result.