Thank you guys.
My new SD card is from SanDisk. It says UHS-II with 260MB/s on its cover.
I tried formatting it as FAT32 with no luck, just to see Loadiine GX2 say SD mount failed.
(However everything under vWii is working fine)
Finally the issue was solved by using Panasonic SD formatter...
if they get permission from 4j (the studio who helped put minecraft on consoles), they could put the console edition tutorial worlds in the game, as seeds
and i mean all of them (if not, maybe a few highlights, like TU1, TU31, and TU69)