All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
It is not permissible to watch cartoons that contain evil and religious prohibitions, the most serious of which are those related to faith and Tawheed (monotheism), such as what you have mentioned in the question. It is a great evil and a cause of corruption of faith, especially in children. For more information, please refer to Fataawa 188149 and 238003.
The Muslim authorities must forbid it and the scholars should clarify its ruling and warn against it. If any of the general body of Muslims can refer the matter to the authorities, then they should do so, so that the latter would forbid it and clarify its status in the Islamic law.
Indeed, some citizens of the Kingdom of Saudi Arabia did the same with regards to the cartoon series "The 99". They requested a Fatwa from the Grand Mufti of Saudi Arabia concerning this series, and the request was referred to the Standing Committee for Research and Iftaa’. Then, a Fatwa was issued prohibiting it, and it requested that that cartoon be prevented from being broadcasted, and said that condemning and forbidding it was an obligation.
For more benefit, please refer to Fatwa 117679.
Allaah Knows best.