While they do look similar, this is not correct. The ability shown in the video is actually a fair bit different, which you could probably determine by watching this quick clip a few times and some guesswork. I won't spoil it for anyone, but this early version of Irelia ultimate was actually closer to another spell that exists in the current League game than it is to Yone R.
This thread was added on August 17, 2020, with posts from endstep.
Original Post
https://youtu.be/hZe3gfqzO-g?t=148