Anyone know a good widget or how to implement a blocky video gallery?
I am trying to do something like this:
I’ve been searching online all day but I can’t find anything decent and all good widgets have a monthly subscription so no hehe.
Lots of these on GitHub to be found. 
What is the right name on English for this widget?
You could check out videolightbox. It integrates well into blocs. You can use it for free if you don’t mind a watermark in the interface. You can buy a licence to remove it - at least you can try before you buy.
Thanks! the demos looks a bit from windows 95 no?
It’s quite an old product, but you do have a wide choice of styling options within the app. The best thing to do is download it and give it a try.