Over the past couple of years, Chinese developer have been licensing Japanese IPs to make into mobile games for the local market, even if the IP itself is quite obscure there. Mashin Hero Wataru is not one of those IP, has gamers who grew up in the 80s and 90s still have fond memories of the classic anime series which spawned several seasons. However, developer Kingnet has done a really lousy job in making a mobile game out of it.
FYI, Kingnet is the studio which made the commendable Sword Art Online Black Swordsman: Ace (perhaps a different team). Mashin Hero Wataru has sub-par animations, graphics, sound effects, buggy systems, uninspired game design, and almost everything else was done half-heartedly. Even if this is a gacha-heavy game, I still enjoyed many titles in the same genre. Right now, Mashin Hero Wataru has just scored 3.1 out of 5 on the China App Store after 2 days.