How to tell Yusei and Z-ONE apart (a simple guide for those who can't tell the difference) with pictures!
1. The shirt. THE SHIRT
This should be the most obvious difference. Z-ONE’s shirt has a larger design on it, and is symmetrical, whereas Yusei’s shirt design is not.
2. The helmet.
Yusei’s helmet has a small white arrow on each side of it, whereas Z-ONE’s helmet lacks it.
3. The collar on the jacket.
Yusei’s jacket has round bubbles on the collar, whereas Z-ONE’s has small rectangles.
See the above images for this as well.
4. That metal plate thing.
Obviously Yusei lacks that, and Z-ONE only has it to emulate Yusei’s personality.
TL;DR: Z-ONE’s cosplay needs some work.