The complete question would is “is the Su-35 superior to the F-16 in X,” where X is the mission.
On the surface, the two are radically different aircraft.
Picture from this web page, How to Shoot Down a F-22? shows the size difference between the Su-27/30/33 Flanker family, where the Su-35 is derived, and the F-16.
The Su-35 is the newest version of the “Flanker.” It is a large and heavy 2-engine fighter weighing 17 tons empty. Its design is from an air-superiority fighter (implying it carries a powerful radar and expensive armaments optimized to shoot down other fighters). The large size means its range is longer than other fighters (combat radius - 1500km). The closest fighter in the US inventory is actually the F-15.
There have been only several hundred Su-35s built (although the older Su-27 is much more numerous). Sukhoi Su-35 - Wikipedia
The F-16 is a much smaller fighter. It has 1 engine and weighs 8 tons, half the weight of the Su-35. It started as a lightweight highly maneuverable fighter but grew into a slightly heavier multirole fighter. The smaller size means it is not intended to fly long range missions (combat radius 500km). The Israeli Air Force did use them to bomb a nuclear facility in the 1981, Operation Opera - Wikipedia, but that is an exception. The F-16 does not have the large radar that the F-15 or Flankers would have.
It is a best-selling fighter among American allies. It is extremely versatile, flying both air to ground and air combat patrol. Thousands have been produced. It has flown most of the combat missions of the US Air Force by far. General Dynamics F-16 Fighting Falcon - Wikipedia
There is little meaningful comparisons between these fighters. If an Air Force was considering purchasing Flankers, the F-16s would probably not fit the mission. For example, the Su-35s can carry extremely long range missiles designed to attack AWACS and air tankers. The Americans do not make such missiles but even if a country that flew F-16s developed such a missile, it probably would be too large for the F-16.
On the other hand, an air force shopping for an F-16 would consider other shorter range multi-role aircraft (perhaps the Gripen). This class of aircraft is usually much less expensive and easier to maintain. I am not sure if the Su-35 has ever been used in ground attack. The F-16s are one of the best ground-attack aircraft created.
If a flight of Su-35s and F-16s had to fight, the side with AWACS will usually win. The AWACS will vector their fighters to attack from an angle that avoids the detection by enemy fighters. No matter how good your fighters are, if they have to fight an adversary with AWACS without their own support, they will be like a former boxer who has gone blind being attacked by a street gang.
In general, the air commander with an AWACS and heavier fighters carrying more long-range weapons and greater combat radius will have more freedom than an air commander who has an AWACS and only smaller fighters. If both sides fight without AWACS, the larger fighters have the advantage in Beyond visual range(BVR), but only a slight one.
If the Su-35 and F-16 engaged in a dogfight in the manner of Mig-19s vs F-4 Phantoms over North Vietnam, the F-16 has the advantage due to its extreme maneuverability. A Su-35 pilot will use its high speed to disengage if he can.
