The “match” string need to be translated from the BP Search Profile plugin, as you have discovered. That plugin doesn’t provide a POT file, so we created one with all the strings from that plugin which you can download here:
Once you have translated the strings you need, you should have a
bp-profile-search-en_US.po file that you will place in the
wp-content/languages/plugins directory of your site. For other languages than English, please replace
en_US from the file name by the language code of your choice, for instance fr_FR for french.
Please keep us updated if this helped you with the translation of your website.