Migrate cold database (freebsd) to mariaDb on ubuntu

I have a little bit of a pickle: I have a freebsd based jail that ran nextcloud with mysqldb The machine running the jail is broken. I still have the jail with the data. Now I was wondering if I can get the previous database over to an ubuntu VM with the current version of mariadb (I don't know what version was running on the freebsd jail) Can anyone tell me how to do this? Tried copying the DB files over but either mysql wouldnt start at all or no tables are available in the DB Any help appreciated. I'd assume at least some other files are required to get that back up and running best regards