if you are searching for OST to PST conversion tool this is helpful for you
The best OST to PST converter should support big OST files, maintain email attachments and folder structure, and have an intuitive user interface. Because it lets users select the necessary files or mailbox items for conversion rather than processing everything, a filter option is particularly crucial.
TrustVare OST to PST Converter is one choice worth taking into consideration; it provides a filter option to assist users in choosing the necessary data for processing. By removing extraneous items and concentrating on the facts you truly need, this can facilitate migration.
check the resulting PST file before converting to make sure your important emails and attachments are kept safe.

I tied CubexSoft EML Converter to import EML files into Thunderbird profile. I am pleased with the service and recommend this utility to all the users who want to import EML files into Thunderbird. The software quickly save entire EML mailbox along with attachments in Thunderbird account. No changes will be done in mail properties of EML files.