Couple of questions - Flex

I really enjoy Grav. Very fast and modular CMS.
To my questions.
I have created a Flex directory with a lot data. I also use taxonomy and i want to search for them but if i search for like “Car” it won’t show up.
In the directory folder inside the template folder of flex i defined it.

Also. What would be the easiest way to have a multilanguage in flex data? i though about two ways.

  1. Add to file Extension the language code like in the .md files.
  2. Or just create a new key with like de, en etc.

How i can choose in which way data is sorted when i load the flex object in the admin panel? I really would like it if it would sort it by id at the beginning.

Can i only allow specific “tags” to be allowed? Let’s say i made a list and defined it. It should only allow those which are defined and selectable.