So with the reverted LeBlanc, I tested her out in Practice Tool just to make sure that she is actually missing something out and it turns out, her Q - Sigil of Malice mark is missing a sound effect for when the mark hasn't been triggered and lasts throughout its duration. In the video, you can clearly hear it. Also the mark is missing a visual specifically those lights that are going outward around the mark.
It's just a bit irritating because I have mained her for years, and I still do, and I always hear her sound effects and I would notice right away when something is off.
Please re add those and thank you :)