How to translate teacher's H5P content thanks to a translation tool?


I’m helping a teacher to translate his content (within H5P activities). I want to use a dedicated translation tool like OmegaT to ease and speed up the process quite a lot.

OmegaT with the XML filter does not understand the embedded json format and screws it.
What is the right way to do it? What tools should I use?

Thanks in advance!