This movie is very strange and definitely not for everyone. At only 50 minutes long it's very short, but it uses it's time wisely and the film doesn't drag in any places. The ultraman character in this film is a germaphobe and hates dirt, that's definitely the strangest part of the film, he has to overcome is fear of dirt to save the day.
This film is very comedic, it may as well be a straight up comedy, it pokes fun at some of the goofier sides of ultraman and it is not meant to be taken seriously, it is also for kids so keep that in mind when you watch it. The original ultraman cast makes cameos in this and I loved it, Ide is my favorite character from the series and I loved seeing him again, all of the cameos were very funny and I found them adorable, you can tell everyone is having a good time.
Overall I would say if you're an ultraman fan you may as well watch it, it's short and on YouTube, and even if you're not you can still get laughs out of this and the final fight is actually really entertaining.