Do Memorium haven't get updated yet?
I saw text “new sprite added to the memorium” and other things, but when I check there, everything still locked
Depends on where did you see that! All Memorium entries have to be unlocked by playing the game and clicking the memories (from the colored text) as they appear in the story. Notes on new updates about new sprites being added can mean entirely new sprites for characters (but having/unlocking the memory is still required) or just new variations of sprites that were already visible in the Memorium, but that weren't there to be seen yet.