I got a private message from @carwash338 about a mobi ENG-POR dictionary and it didn't convert....
...so I spent some time with HTML::TreeBuilder and I am starting to create a general purpose html-dictionary converter subroutine. It's still very early and only tested on 2(!) dictionaries.
However, one of those results can be found in the ENG-POR subdirectory on
pCloud.