in the isekai i've seen we have the character/characters live their normal life then (usually) die and reincarnate into another world, there is the early struggle to learn and adapt and so on.
Here there isnt, people build their characters for the game, which start already in the alternate world(there may be a brief prologue in the real world) and they already know the rules of the system , this nullify the surprise and the confusion, sure they can roleplay it, but wont feel it.
If i had to make an isekai game, i'd ask applicants to apply with a character they are currently playing in another game(just background/personality, ignoring the system) and then have the game be an alternate version where their original character die and is reincarnated into the new world(with the other player characters)
now you have characters who have lived past lives and may very well want to return home(my party is fighting the goblin king! my pilot was attacking the death star! hey, where are my godly powers? ecc) and run on different mechanics, which should disorient the player a bit😄