Well that is going to be a list...
You know of the Nelson class all forward arrangement, same all forward layouts:
Richelieu, Donkeruqe - 2 quad turrets forward
Yamato preliminaries: A-140/A,B,C,D,G,J,K, Hiraga's Proto-Yamato 1929 Design, Some of the North Carolina preliminaries like Scheme A and D for example, RN F3, Italian Maricominav Design, Soviet Project 21 - 3 triple turrets forward
F2, Harima Shipyard design for China - 3 twin turrets forward
Tone class - 4 twin turrets forward
IJN Oyodo - 2 triple turrets forward
Victoria - 1 twin turret forward
Itsukushima - 1 single "turret" forward
Others:
North Carolina preliminary design Scheme F - 2 quad turrets aft
Matsushima - 1 single "turret" aft
RN H3b/c - 1 turret forward 1 amidships
RN M2 - 2 turrets forward 2 amidships
RN K3,M3,N3 and G3 - 2 turrets forward 1 amidships
Incomparable Designs - 3 twin turrets amidships
Richelieu Preliminary and one of the Maricominav design - 2 quad turrets amidships (Admiral deFeo type arrangement)
Ansaldo export design for Argentina - 5 triple turrets 2 echleon 3 on centreline 1 forward 2 aft
Hidetaro Kaneda pre WW1 Design - 7 twin turrets 3 on centreline 4 echeleon creating 3-3 turret diagonal lines
Ansaldo design for Russia - 6 triple turrets 2 forward wing turrets 2 amidships wing turrets 2 centreline superfiring pair aft
Fusion Design X4, Ansaldo design for Russia - 4 triple turrets 2 centreline ship ends 2 echleon
HMS Nonsuch, Invincible class - same as above just with twin turrets
Invincible preliminaries, HMS Uncatachable - 4 twin turrets 2 forward wing turrets 2 centreline superfiring pair aft
Some of HMS Untakeable and Unapproachable - 6 twin turret hexagonal layout but all forward
Not unique layout just the number of barrels per turret is unique: Tillman's Design 171 Scheme 2, 6 barrels per turret for a total 24
Does hexagonal layout count as unique?