Let's talk about the major materials that made up the Venera landers. https://space.stackexchange.com/a/9965/25 has a great summary of what the landers were made of, they are composed of include Titanium, gold, fiberglass, KG-25 an high-temperature polyurethane foam, and PTKV-260. There are a bunch of other materials, likely including some glass and other things that have the potential, but a complete list of materials isn't available. Most of those wouldn't work.
The titanium already showed signs of oxidation when the probes were working. It is safe to assume that continued. Gold does not oxidize and should have remained. Any fluids and foams would have likely dissolved, just not leaving much. Aluminum likely remained mostly intact, although weakened somewhat through some extra oxidation, it has probably collapsed. It will eventually succumb to the sulfuric acid. Iron will have dissolved in any sulfuric acid that makes it to the surface.
This paper suggests gold, iridium, silicon dioxide, aluminum nitride, silicon nitride, and aluminum oxide are all good materials to use on Venus. I can't find any reference to any of these being used except for gold, and most likely silicon dioxide. Any of these materials would have survived. Most of the rest would be some kind of oxidized mess, although I do suspect that most of it would at least remain close. There is a slight surface wind on Venus which would have blown away the really badly damaged components, but much of them would have only been oxidized versions of what was already there.
Any parts that did survive would be covered in dust, due to the wind. The images we have seen of the surface of Venus show very few rocks, and most of those are pretty small. It is likely that any light wires would have been blown around, along with the severely degraded components. The glass from lenses would have likely remained, along with at least a part of the electronics, but would probably be covered in dust.
Some of the later missions made use of special materials, which probably helped them survive more intact. I can't find any details, but they seem mostly to have been used for the electronics. Aluminum and even iron will last long enough to serve its purpose on Venus, and the limiting factor never was keeping the structure together.
Bottom line, very little is likely left, and what is left would be scattered and covered in dust.