https://www.reddit.com/r/Higurashinonakakoroni/comments/y4dxal/so_sotsugou_another_end_has_been_released/
Satoko seems to have memories of Looping unlike the usual Gou/Sotsu Satoko which combined with the ending image suggests that she is Lambdadelta with Rika being Bernkastel.
Remember Ikuko Hachijo’s Pen Name(which she gives to Battler) suggests that she is Asumu while her real name suggests she is Beatrice(ouch!).
If the Rokkenjima Massacre is a hint to Ciconia’s Backstory as well as the Backstories of Featherine, Bernkastel and Lambdadelta then I suspect that Bernkastel, Lambdadelta, Gou/Sotsu Satoko, Gou/Sotsu Rika, Gou/Meguri Satoko and Gou/Meguri Rika are all representations of Battler, Tohya Hachijo & Ange.
Battler detaching from Beatrice only to appear grasping her hands and merging with her represents Bernkastel giving her powers to Featherine, Battler’s buried Memories represents Umineko, Tohya Hachijo(the Battler version) represents Gou/Sotsu/Meguri Satoko & Gou/Sotsu/Meguri Rika while Ange represents Bernkastel & Lambdadelta in their Hinamizawa Bodies.
We know that Asumu’s demise was supposedly due to Rudolf so the King of Ridicule from Ciconia must have broken Featherine’s Horn leaving her in a child status while leaving her disconnected to Bernkastel until she got a physical Body brought in which would allow her to inhabit both a Rika Body and her Bernkastel Body.
Eva represents Eua. That says a lot about the children of Kinzo if one of them is of the same species as Hanyuu! Then again Krauss & Rudolf represent 2 of the 3 Kings from Ciconia from the looks of things…
Kyrie therefore must represent Hanyuu. Hanyuu as we know is the one who gave Rika Looping Powers creating Bernkastel. Featherine was Bernkastel’s master and considering Asumu was a Stepmother who raised Battler in his mother Kyrie’s place…
Hanyuu spent a lot of time with Rika so she would naturally assume Bernkastel was Featherine’s creation due to not being told about her by Rika.
The question is: in what manner did Hanyuu carry out the Rokkenjima disaster? Most likely by scrambling people’s memories! Make Maria think she is Hanyuu, scramble Featherine’s manifestation within Miyao Mitake while kicking out Lambdadelta sending her back to Hinamizawa, shoot the King of Wrath’s face off, wipe Kumasawa San’s Memories, wipe Rosa/Chloe Ironside’s Memories, etc.
Since Kyrie is suggested to kill Lion Ushiromiya who is implied to be Featherine manifesting in Vier Dreissig I suspect that Seshat is calling in Hanyuu and Eua to wipe all memories again.
Edit: Just realized the possibility that Lambdadelta is infact Rika Furude and that Ikuko Hachijo(blatantly Beatrice whose name Sayo means 34 I.E. Lambdadelta) represents Rika finding Bernkastel without Memories while Featherine as Tohya Hachijo represents a Fictional Character in the Sea of Fragments treating Ange/Bernkastel as a Cat.
The Fragments of the Sea of Fragments are called Memory Fragments after all.
Edit 2: https://www.reddit.com/r/Higurashinonakakoroni/comments/y60m4g/higurashi_gousotsu_another_end_summarytranslation/
A proper translation and it seems Lambdadelta is not Satoko but the Game Master of the Gameboards.
Makes it sound like she is Eva with Satoko being George(with the King of Wrath being Lambdadelta’s assistant in creating Witch Satoko). That logistically means that Eua is Maria Ushiromiya who is on good terms with George despite making fun of everyone.
Sakutaro in that case is Higurashi Gou Hanyuu whose form is taken from Eua’s creator Hanyuu.
That all leads to questions on who is the Game Master who created Lambdadelta and Hanyuu…