Actual bodies:
Byakuren with Benben body
Yoshika with Yatsuhashi body
Shou with Suwako body

Missing:
Suwako head
Shou body
Byakuren body (probably Suwako head)
Yoshika body (probably Chen)

fortunachan said:
Missing:
Suwako head
Shou body
Yoshika body (probably Chen)

I don't think Chen can get in on these shenanigans as she doesn't have a last name.

FJH said:

Moriya head with Miyako body

Tsukumo head with Toramaru body

I don't think Chen can get in on these shenanigans as she doesn't have a last name.

I didn't read the rest of the comics. Which is convenient here. Without spoilers, here's what you can infer so far.

?.K > K.Keine < K.Kyouko > Y.Kanako < Y.?
Y.? < Y.Yukari > H.Yuugi < F(H).Mokou > H.Meiling < H.Akyuu > S.Aya < S.Shinmyoumaru > I.Sakuya < I.Kasen > H.Kaguya < H.?
H.? < H.Byakuren > T.Benben < T.?
T.? < T.Shou > M.Suwako < M.?
M.? < M.Yoshika > T.Yatsuhashi < T.?

H.? < H.Raiko > H.Reimu < H.Kokoro > K.Koishi < K.Marisa > I.Momiji < I.Suika > K.Sanae < K.?

?.Y > K.Youmu < K.Nitori > H.Nue < H.Tenshi > I.Tewi < I.Kagerou ? F.Mamizou ? ?.? ???????

You'll have to look up a character list for all the characters with the appropriate surname or given name that would continue these mess of chains. It gets confusing when people order the names in the western order and I think they ordered it in the original way.

Here are the possibilities other than those already in the above list, excluding western names and.
A.Minoriko, A.Shuzika, K.Ichirin, K.Seija, K.Youki, K.Yuuka, M.Futo, M.Kosuzu, M.Minamitsu, T.Kogasa, T.Miko, T.Soga, U.Renko, W.Toyohime, W.Yorihime, Y.Eirin, Y.Ran

Byakuren's body could be on Kaguya or... maybe Mamizou. Well, that's all I got. I guess the (F) in Mamizou's surname could be an H instead?
Yoshika's body could be on Suwako, Futo, Kosuzu, Minamitsu, or Rinnosuke.

Chen already appeared and she's normal smh