Can rusting of chain be slowed?
We don’t give specific product recommendations but the following general advice should help reduce rusty chains:


don’t store your bike outside. If you do, put it under a breathable cover. Morning dew is a considerable source of moisture so check your bike in the early morning to see if it’s wet. 
wipe down your chain after it gets wet. Having a dedicated shop rag for your chain helps
if your oil-based chain lube washes off too easily, try a wax-based lube or vice versa. Ask the staff at your local bike shop what they recommend for your local climate and terrain
if all fails, try a chain that has corrosion resistance as a feature. Note that nothing is corrosion proof and you’ll still have to do all of the above


Or, accept that some degree of rust is part and parcel of having a working bike (as opposed to a display bike), note that rust only accumulates on the non-moving and non-wearing side plates of the chain, keep it lubed where it matters (internally on the bearing surfaces) and be happy.