Can I use full-size 64/72 bit DDR2/DDR3 memory module with CycloneV hardware controller of 24 + 24 bits?
No, you can't.
You are only taking into account the data pins, but a DDR has other pins, address and control. Each one of the two banks has its own address and control pins. You cannot merge them together.
You are limited to a maximum data width of 24 bits. And even if you decided to limit yourself to 24 bits, there are other considerations on how you can connect a DDR interface to a device, as opposed to a DIMM. You have to check other pins compatibility, timing, clock, etc.