Hello,
You can solve your problem using given methods:
Method 1: Using Outlook
When you export the Inbox mailbox file in CSV file format, a CSV file does not store send/receive date within emails. A CSV(Comma Separated Values) file used to Import and Export contacts in form of spreadsheet or database in Outlook.
To get back your email with send/receive date properties within same email clients. You can directly import PST file which holds contacts.
Method 2: Using Thunderbird
To Move PST file into other email clients(Thunderbird). You have to convert default file format of Outlook into Thunderbird. To see your emails with send/received dates, move Outlook PST File to Thunderbird.
You can use a manual method or any third party utility tool to convert PST file to MBOX
PS: Try the demo version before moving further.
Hopefully, it will help to solve your issue.
Thanks and Regards
Anjleena