There are a ton of tools available for converting Lotus Notes files to Outlook PST files. Additionally, I'd like to recommend
vMail NSF to PST File Converter Software. Before saving, this software displays all of the flexible emails in preview items. You can verify a few of your chosen emails in the preview items. The user stores their emails, inbox, sent things, draughts, deleted items, and attachments separately from NSF in a variety of file formats, including PST, MSG, EML, EMLX, and MBOX. Use the tool's free trial version to preserve up to 10 emails at no charge. All MS Outlook versions, including 2000, 2002, 2003, 2008, 2010, 2013, and the most recent 2019, are supported by the tool.
Get more info-
https://www.vsoftware.org/nsf-to-pst-converter.html