Doraemon: Robot is a bootleg film made in 1983 based off the popular anime from a Taiwanese animation company. I've tried to find the film with no luck, and the company's website hasn't been up since 2007 according to the Wayback Machine.
I remember watching a anime show with ninja kids in spain tdt channels (i don't know if is Clan TVE or Boing). I have a photo of it, but it's on my mom's old pc.
! Thanks for the feedback, seems it might be a lost short after all! I'll just have to find a way to upload it as it was recorded onto a DVD. It's so weird to think that some show I used to see constantly is now a part of lost media o-o
Rip the DVD with Handbrake. Upload content to YouTube and Vimeo (as backup)