There are some situations on the water where bass may act more like a trout, selectively feeding on a hatch of dry flies or keying into a specific hatch of insects. Other times trout may act more like bass, gobbling up anything resembling food that drifts or swims by.
Different bodies of water and different fish all have their own characteristics. It's hard to make a generalization about fly fishing for a specific species that's always going to be the sure-fire way to go about catching them. The best way to approach a new body of water and species is to be as observant as possible and try to take in as much as possible about what's going on. If the water seems dead or lifeless, tie on a streamer and actively search for a player.
Characteristically, bass are ambush predators much more so than trout. They will find a good holding spot, behind a boulder, under lily pads, or tucked into woody debris, and typically lay in wait for smaller baitfish, insects, or even frogs to swim by. They will then surprise their prey and attack with high-energy burst of speed to stun and kill their prey.
A stout 6WT fly rod is a good weapon of choice for chasing both smallmouth and largemouth bass. Generally, floating fly lines are used when trout fishing. If you decide to give bass fishing a try, you may want an extra spool for your reel line up with a full sinking or sink-tip line. Since streamer fishing for bass is typically the easiest and most productive way to locate and catch bass, a sink tip line will really come in handy.
A trout fisherman's fly box is largely filled with insect replications; tiny midges, mayflies, and caddis in both nymph and dry fly forms. A bass fisherman's fly box will mostly be filled with streamers, both realistic representations and gaudy, flashy impressionistic style patterns.