The easiest approach to get Outlook MSG contact files onto your iPhone is to first convert them into a format that your iPhone can read, such VCF (vCard). You can't straight away open MSG files on an iPhone, therefore you need to convert the format first.
To complete this conversion process without any hassle, you can use the
MSG to VCF Converter software. It rapidly and easily
convert MSG contacts to VCF format. When you move contacts, it makes sure all of the information, such their name, email address, phone number, and address are preserved. After you convert them, your iPhone will be able to simply find and import these files. This method is quick and does not need you to enter data manually, which might lead to mistakes.
You can also refer this Video guide, that can help you in performing the conversion process-
