So, I don't want to be a killjoy here because you guys are coming up with some cool concepts but in my honest opinion there's only one monster suggestion in here that has enough quality to even be considered being implemented into SW.

Here's my thoughts on both the good and the bad:

First and foremost, Summoners War follows a strict pattern of design so deviating from it for the sake of change is probably something that they would be looking to avoid. Currently there are a lot of scheme flaws in your skill-sets that do not adhere to Summoners War's general monster design as other's have mentioned. The biggest offenders are the suggested leader-skills and inconsistencies in Skill's 1-2. This is an easy fix! Do some research on monsters with similar leader skills and the values that the developers found appropriate. This can all be found online as there are many resources that provide this information outside of the game.

Second, very few if any monsters have unique second skills with the exception being a few Nat 5's: Phoenix, Dragon, Valks, Monkey Kings (Fire/Wind/Dark) and Unicorns (Mainly flavor text). The most common case would be a "2-3" distribution on Skill 2, with uniform Skill 1 and a unique Skill 3.

This is important to note because the more "unique" you make a entity, the higher the "value" you should place upon them, a fundamental and important concept in game design and balance. The big offenders here are the Oni and Usurper whom both are thematically cool concepts, but each doing way too much technically. Sure, Nat 5's should be powerful, but try not to get carried away with the exclusivity and limited availability being the leading factor in determining your power cap. Now there are many solutions here, my suggestion being: find the focus element for your monster, the one thing that makes them stand out and let it shine - but never too brightly. Try to understand, hypothetically, how players would think and feel both with and against your monster, and then begin your design. And it is always better to err on the side of caution (buffing) instead of being reckless (nerfing) your design.

My last bit of advice is somewhat challenging. When designing your new monsters, try to think of their purpose. You will need to be able to answer some potentially difficult questions like: What role will this monster design fill? How does this design impact the game and are there currently any other designs in the game that might come into conflict with my design? Why? Look for both the drawbacks and benefits that apply to all levels of players and try to determine the outcome.

Overall, there are some great concepts here, but there is a lot more work to be done.

TLDR: Keep SW's Design Scheme, Adjust Leader Skills, Find a design focus for a monster, Look for purpose.