PyCharm - IdeaVim - “sneak” plugin : how to remap 's'?

Question

I\'m using PyCharm 2020.3.3 on Windows, with IdeaVim 0.64 and IdeaVim-Sneak" v 1.1.1 : https://github.com/Mishkun/ideavim-sneak

The default key for sneak is \'s\' bu