Many Sonder sprites will be useful, but not all - for example there will be no "prisoner" outfits (so I need to change player face, and also use the intermission animation). Also I'll have to change the scenery into "city/ghetto-like" rather than camp-like, and make "urban" backgrounds instead of current ones.
So it's alot of work, but I think I should tart working on that. So when Sonder will be finished I'll already have the engine and the graphics and will need only mapping
P.S. btw the third sequel in the series (and probably the last one) will be probably (logically) named "SonderKommando 3 - Treblinka confrontation", as jews from Warsaw were contantly transported to Treblinka extermination camp - so our heroes should go there after taking care of Warsaw Ghetto.