I have actually thought a little about this TL's version of Kaiserreich in the past. It probably wouldn't be called "Ciesoriaus Imperija", in my opinion, as that would imply a Lithuania-centric mod, while, in my opinion, such a mod would almost certainly be focused on France. Maybe "Frankreich"? Assuming the idea for the mod popus up in German-language Internetwork.
France would definitely be the German Empire of this world, sitting content with a reannexed Rhineland and North Germany turned into a puppet confederation, at least until Potop-style troubles start appearing.
Lithuania would likely be a combination of KR Russia and Austria. A nominally very powerful, but practically fragmented and weak nation with a hated leader who's about to die (Emperor Žygimantas). The Lithessia proposal could get brought back up in a counterpart of the Ausgleich as a possible way to save the Empire from collapse, or alternatively, a Slavic rebellion could break out and destroy it, or Lithuania could go democratic, Unitarian or extremist.
South Germania and Visegrad could fill the role of the Synditern, the former as a Unitarian republic and the latter as Samsa's CUS. I could also see the mod having countries such as Sweden, Spain, the Ottos (assuming they don't go Union) or maybe even Italy giving an option to go Unitarian.
The Mughals could also fill a similar role to Lithuania as "a Pyrrhic Victor which can either collapse ablaze or recover and become a world power". Expect the Nijasure brothers or other prominent Indian Unitarians to make an appearance there.
Not sure where China and Japan could fit. I can't really imagine China as the type of nation to receive the KR USA treatment and go through a four way civil war, although I don't discount that either. But, then again, the interwar period also saw China go through extremist and Revivalist-influenced coup attempts, so that would definitely make an appearance as well.
