I recently watched episode 14 of Tokyo Ghoul: re and in Kaneki's fight with Arima, he used a Kagune that was really different from his usually Rinkaku.
Do Ghouls gain the kakuhou they eat when they cannibalize?
I recently watched episode 14 of Tokyo Ghoul: re and in Kaneki's fight with Arima, he used a Kagune that was really different from his usually Rinkaku.
Do Ghouls gain the kakuhou they eat when they cannibalize?
There was no indication (at least in manga) that they do.
Kakuhou type is determined by its position in body. And even if ghoul eats flesh of another ghoul, it serves only as supply of RC cells. There is no logical way it would affect arrangement of kakuhou in ghoul body. Or add new one.
Regarding custom kagune - kagune form doesn't depend on kakuhou, only its core properties do. As mentioned by Eto, form of kagune is limited only by imagination of its owner.