[@TruckKun]

Here are some weaknesses that I found on a superpower wiki.

-Distance, mass, precision, etc. depend upon the knowledge, skill, and strength of the user, and their power's natural limits.

-Light Manipulation, Light Generation, and other light based powers are especially effective against this power.

-As shadow is a dark area produced by a body coming between rays of light and a surface, light may strengthen shadow magic or may even be a requirement in some universes.

-May be unable to create darkness/shadow, being limited to manipulating only from already existing sources.

-May have to be in sync with darkness, whether their own or the source of their power.
May become affected/corrupted through extended exposure.
Umbrakinetic Immunity/Shadow Absorption

I am unsure if any of these will help you, but i do hope it does. As for names here is a website i use for name generation. 

[url]https://www.name-generator.org.uk/?i=26xn2aix[/url]