Is it possible to play Borderlands the pre-sequel campaign four players with two players on one PS3 and two players on another?
According to this article the game supports two players per console (couch co-op) and four players either on LAN or in online co-op.
How many players can play Borderlands: The Pre-Sequel locally (couch co-op)?
On consoles Borderlands: The Pre-Sequel supports two players in couch co-op.
How many players can play Borderlands: The Pre-Sequel via system link or LAN?
Four players are supported in LAN play on all platforms.
How many players can play Borderlands: The Pre-Sequel online?
Four players are supported in online co-op.
How many players are supported in combo co-op?
Two players per console are supported with any combination of online players for four total online.
if it works the same way as the Xbox 360 then yes should be able to do so with an Ethernet cable connecting the two consoles and having your network settings set to system link, (I believe it can also be done through a modem without using any data) on the bltps start menu press back on xbox to get network options - would imagine its select on ps3.
it definitely possible, as this is how I play with my friends every night,( I don't have a reliable internet connection) and we have just all hit lv 60, loads of fun :) good luck.
note: as you probably realised you would also need two copies of the game