Two more Bismark class battleships weren’t going to turn the tide even against the Royal Navy, which had 15 battleships and battle cruisers in service at the start of the war and another 6 were commissioned during the war. Constructing them would also have been an enormous waste of steel and man-hours for Germany, diverting production from much more useful items such as tanks and submarines.
I must object to the use of the word ‘obsolete’ to describe battleships during World War II, however. They lost their place as the queens of the seas to the aircraft carrier, but they were far from obsolete and were still capital ships. In the Atlantic, bad weather and long nights further north could severely restrict the usefulness of aircraft carriers. The aircraft carrier HMS Glorious fell to the German battle cruisers Scharnhorst and Gneisenau in just such a situation. The Scharnhorst herself met her fate at the guns of a British battleship off of Norway. In the Pacific, night surface actions were very common, happening more frequently than the rare carrier duels. On those occasions when battleships were risked, they could be decisive. Three Japanese battleships were sunk by naval gunfire and torpedoes, and a fourth was so badly crippled that it could not escape from land based airpower come the morning. Battleships also provided a sturdy platform upon which to mount enormous numbers of anti-aircraft guns. They were also undisputed when it came to providing bombardment of shore targets. US forces on Guadalcanal were subjected to a number of bombardments at night by cruisers and destroyers, but the one occasion when Japan was able to run two battleships down The Slot to shell Henderson Field unmolested at night, it was known to the marines and soldiers ashore simply as “The Bombardment.”
Regarding the OP, these two givens alone virtually doom Germany:
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That, no matter what Germany does, Japan will bomb Pearl Harbor in late 1941, bringing the US into the war.
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That Hitler, being Hitler, will at some point attack Poland(bringing the Western Europeon powers into the war), and later invade Russia.
Germany’s only hope for shutting down the Western Front would be a negotiated peace with the British, which wasn’t likely to happen. The invasion of Russia as it was historically carried out was extremely successful, but even if it was more successful and Moscow and Leningrad fell, a capitulation by the USSR isn’t a given as a result. On its own the invasion of Russia almost certainly doomed Germany to its eventual defeat. The idea of getting Japan to start up a second front against the USSR as mentioned by xtisme has a couple of problems with it. Japan turned south to attack the Dutch East Indies in 1941 in order to secure the oil it needed to continue its ongoing war on China after being cut off by embargo. Turning instead against the USSR would have left Japan with a major oil crisis looming on the horizon. The other problem is that Japan came off very badly in border fighting with the USSR in1939; the conclusion of a US Army college study on it and Japan’s mistakes and deficiencies in the fighting is located here.