Implementing a SN74LS245 Octal Bus Transceivers With 3-State Outputs in Logisim
I know this post is pretty old, but may be somebody is still interested.
Indeed, it is not possible to really simulate the 74245 with Logisim : in a subcircuit, a pin may only be an input OR an output, not both, as opposed to the real 74245.

But it can be simlated pretty easyly.
First of all, you design it as a subcircuit, where for each pin A1, B1, 12, B2 etc. you create 2 pins : one input, one output :



Then, you can build your circuit with it. In the following, its a typical usage where you interface a data bus with a register.



When FROM A TO B is set to one, you can write some value on the bus using the BUS INPUT pin, then assert the bus. Signals are going from a to B.
When done, you just push the button below the register to store the value.
Then you can stop asserting the bus, and switch FROM A TO B to zero : one can see that now, the bus is written from B to A.

Not perfect, but the easiest I can think of to "simulate" the 74245.