"be varied with" is correct and usable in written English.
You can use this phrase when you want to express that something is replaced by something else. For example, "The type of exercise I do can be varied with swimming and walking."
Since the consumption of C6/C5 sugar mixture depends on the composition of the two strains used in the culture, the optimal cell ratio of co-culture can be varied with varying composition of sugars available in different sources of biomass feedstock.
Often, this would be varied with Western fare like pasta and baked beans; one day we even had homemade pizza.
The pumping load can also be varied with Deriaz-type units, which cannot be done with a Francis runner.
Sliced tomatoes, mozzarella and basil also fall into the basic category, but even that mix can be varied with great results.
Parts of speech may be varied, with an adverb becoming an adjective ('You're acting a little overly, aren't you?'); or an adjective a noun ('Love makes you do the wacky').
The biosorption capacity was found to be varied with temperature.
The restaurant cuisine is varied, with a Jamaican twist.
Smuggling methods are varied, with drugs being carried in container cargoes, cruise ships, fishing boats, yachts and aircraft.
The worksheets that came back from the boys were varied, with some showing that boys, too, are clearly affected by pressures around idealised male body image.
The relief structure of Warmińsko-Mazurskie is varied, with numerous postglacial moraines and hills along with thousands of lakes.
Of course, the picture across this vast country is varied, with tight conditions in some places and oversupply in others.
