I tried following the
Larian guide to dialog editing. After trying to follow the described path to the dialogs files, Lohse dialogs, several time only to end up at some dead end, I finally found them.
It seems that the path on the wiki,
Data\Mods\DivinityOrigins_1301db3d-1f54-4e98-9be5-5094030916e4\Story\Dialogs\Tutorial\TUT_LowerDeck_OriginLohse.lsj
, is wrong. It should be
Data\
EDITOR\Mods\DivinityOrigins_1301db3d-1f54-4e98-9be5-5094030916e4\Story\Dialogs\Tutorial\TUT_LowerDeck_OriginLohse.lsj
Again I'm a noob at modding so I might be wrong, or did something wrong in the first place....