Sweden was neutral during the cold war. As far as I understand the Soviet Union respected that on the diplomatic stage. But there is a difference between what you say officially and what you tell your soldiers.
(next three paragraphs try to explain my anecdotal reasoning behind this question)
A few years ago I heard a radio documentary that talked about Soviet spying on Sweden. One thing mentioned was that someone bought an old decommissioned Soviet military ship from the Baltic sea and it had images with silhouettes for visual identification of targets. It had a category for Poland, East Germany and NATO. Swedish ships were listed in the NATO category.
Another tangentially related thing I read in a book by Viktor Suvorov (I understand that historians think he's a nutcase, but this was a spying book, not his alternative WWII history book). He mentioned that when he was invited to watch a NATO military exercise he asked his hosts why some vehicles had red crosses painted on them, it just made them easier to shoot. He was a well-educated tank company commander and was never taught that shooting red crosses is bad.
This makes me think that a political/diplomatic stance on neutrality (or other rules) means nothing in case of war if it isn't part of the actual military doctrine. The decisions on whom to invade are made on higher level than a tank company commander, but he decides which vehicles to shoot in the field. In case of the ship if their orders are to shoot NATO ships and Swedish ships were on the NATO list, then I don't see how any amount of diplomacy will prevent an itchy trigger finger.
What was the Soviet military plan for Sweden during the cold war? Was it considered to be just yet another NATO country? Considering all the spying the Warsaw pact did in Sweden there must have been some plans, but are there documents that have come out that show what those plans were? Invade first? Invade last? Assassinate all leadership and leave alone?
I can't speak of Soviet intentions, but looking a NATO defense plans and estimates gives you an idea what the allies expected based on their intelligence services. This information is at least relevant for the early cold war, 1950s.
In the event of an invasion of Scandinavia, the expectation was that Denmark would be attacked first, and used to control the Baltic approaches and serve as a launch pad for further attacks. At this point NATO planned for two scenarios: the ussr attacking just Denmark and Norway, and the ussr attacking all 4 Scandinavian countries.
Against Norway, the main thrust would go through Denmark heading north to Oslo. Once occupied, Sweden would be completely isolated from the west and would either slowly or forcefully come under Soviet influence. After all, Sweden would go from being in between the two blocs to wholly surrounded and dependent.
A second scenario counted on Soviet military power attacking all at once. Finland would either be "convinced" or attacked, and Sweden would be invaded from both Finland and Denmark with an estimated 10 divisions attacking from the south and 5 from the east.