Remy hansen is a paul gilbert impersonator and has released 3 video on his style of guitar and was wondering how he got synchronized and his right hand technique
It’s looks like he’s using a Wrist+Forearm USX Motion with either swiping or pickstroke displacement
You’d learn it the same you would any motion. Assume a similar setup to him, try picking really fast on a single string and make adjustments as you go with the aim of trying to achieve some level of smoothness. Then, slow it down around 20%, work on it for a little bit before trying to speed it up again and see if it works, repeating this until the motion is learned.
Troy explains it all here:
Also, I found @qwertygitarr’s video on his picking motion really helpful when trying to learn this type of approach so it might be worth checking out