I am desperate because Houdahspot does no more search in Apple Mail. I have around 250,000 Mails to search into. Is there a workaround to import those mail to another app which Houdahspot can use for searching?
HoudahSpot uses Spotlight; Apple Mail emails are searched with CoreSpotlight, which no third party app can access. Spotlight searches files on your computer, databases (in this case an email client database) aren’t searched.
EagleFiler may work, and was designed mainly for an offline email archiver. An Apple Silicon version has been promised for a long time, but SpamSieve development took priority for years. Now Michael is priortizing EagleFiler development.