ez https://www.sokobanonline.com/play/community/akainamill/c-1-60/127565_c11

easy https://www.sokobanonline.com/play/community/boxmaster1369/1519_just-push-it

medium easy: https://www.sokobanonline.com/play/community/mikearcher/colours/6525_easy-rotate
(press shift)

probably hard: https://www.sokobanonline.com/play/web-archive/brian-damgaard/yasgen/126412_yasgen-11

very difficult: https://www.sokobanonline.com/play/community/jeffrey/anguished/1853_anguished-11