This seem all to be Aichi-floatplanes. The smaller black one is a Aichi E11A, the bigger an E10A. Both were used for night reconnaissance (hence Sendai's interested look). The white farthest left seems to be a Aichi AB3. The one with the green fuselage and white wings is probably a Aichi Experimental Type -15 -K0 (Mi-go). The plane left of Hyuuga's head is a Heinkel HD 25, built by Aichi as Type 2 Two-seat Reconnaissance Seaplane.The plane under Sendai is a E13A and the E16A is flying into our faces. The white one touching the Seiran is therefore probably no Mitsubishi F1M.

sanitaeter said:

This seem all to be Aichi-floatplanes. The white one touching the Seiran is therefore probably no Mitsubishi F1M.

I MAY be incorrect: The plane above the supposed F1M is perhaps a Nakajima E2N. But I still think that it's no F1M, because the cowling and the fin have the wrong form. It is more likely a Nakajima E4N2.
The Plane I 401 is looking at could be a Yokosuka E14Y1 (launched from submarines). So it's definitely not only Aichis.

The camouflaged plane above the wing of the Seiran is probably a Nakajima E8N1.

What I identified as an Aichi AB3 (white, farthest left) is more likely a Navy Type 96 Watanabe E9W1 "Slim". But that doesn't make sense, because the plane above it is possibly a Yokosuka E6Y1.

If the picture displays a "tech-tree", than the plane after the E6Y1 and before the E14Y1 should also be made by Yokosuka.

Added some notes
but WWI-era seaplanes aren't written in kanji, so I cannot read

ORZ_passerA_tw said:

Added some notes
but WWI-era seaplanes aren't written in kanji, so I cannot read

I identified two of the WW1-planes (The one with the green fuselage and white wings is probably a Aichi Experimental Type -15 -K0 (Mi-go). The plane left of Hyuuga's head is a Heinkel HD 25, built by Aichi as Type 2 Two-seat Reconnaissance Seaplane). I would add notes too, but don't know how. I tagged most too, but used another nomenclature than you.

I finally identified the plane in the upper left corner. It's a Maurice Farman seaplane. They where launched from the Wakamiya ( https://en.wikipedia.org/wiki/Japanese_seaplane_carrier_Wakamiya ) during the siege of Tsingtao.