Have cable winches, fuel line winches and combo winches. Right now, transferring fuel through a lifting cable seems hard to believe, even for KSP.

Just making winches with a yellow cable that allow fuel transfer, winches with normal black cable without fuel transfer for lifting, and a large combo cable (yellow and black).

Fuel cables would have a lower cableSpring value (not made of lifting), and combo cables would be fatter (cableWidth set to 0.08 or something), with slightly lower cableSpring (weaker) connections. Larger cable width's would also mean slower motor speeds and/or use more power

Already thought about that, but how will work the magnet ? It used for lifting, however it need power to run, so it need to be docked to the vessel. What type of cable will need to be used ?

Also, having different winches for different uses introduce a lot more parts. So we will need a radial, stack, etc.. version for each type. I think it will be better to keep the part count as low as possible, and keep it simple and versatile.

So, I ended to think that realism is not really the target of the mod. Let's say that the cable is renforced by a nano-composite kerbal structure so it can also be used for lifting ?