So lets just go with the British decisively winning the battle of Denmark Strait and sending Bismarck to the bottom of the sea.
What is the effect on British moral, now that they've crushed Germany's super boat without losing their flagship? Is there any effect on the development of air-naval doctrine without the Bismarck being crippled by a biplane? What effect does this have on German moral, their most advanced ship being bested by a WWI design (and company)?
Okay, well let's say Tovey told Holland to put POW in front, Hood and POW find the range, start pounding Bismarck.
Norfolk and Suffolk come in and pound PE to bits too.
Firstly, it means Hood survives. It raises thd question if she gets an Emergency Refit, where they do as much work to her in the shortest time possible.
Maybe send her to America, better AA, Admiralty FC, take as much weight off her as possible. An 8 month refit is likely.
Now, you say what souls be thd effects of having Bismarck sick by a WW1 design ship.
But Bismarck was a modified WW1 design herself. The Germans had believed Hood was a very powerful ship, so they will probably paint it as the fact that she was outnumbered, and outgunned. Deep doen it has an effect on German Naval Moral, but Hitler might not go as batshit crazy over it as he did, due to her going down in a gun brawl Sith the Pride of The Royal Navy, and the Navies newest battleship, rather than bring crippled by an obsolescent biplane. Will he send Tirpitz out? Maybe, but likely with a heavier Escort, like the twins.
It means that Tirpitz will be facing Hood, KGV, DOY, and later Anson and Howe if she tries to break out. And Hood now had the reputation of killing Bismarck.
As for the whole air thing, I'm not sure. I don't think it will have a massive effect on Pearl Harbour, as Taranto had already shown what could be done.
It might slow the end of the Battleship, maybe Lion and Temaraire get finished, but it's unlikely.
British Moral is High. Their Flagship had beaten the Bismarck, and her overexaggerated power will be pushed even higher. It probably gives Britain more faith in their navy, bug not a massive deal more.
Churchills determination to Sink Bismarck post Hood and her ultimate Destruction gave Britain faith in its navy anyway. Hood might be used as a Symbol, The Old Battlecruiser Beating Germany's Newest Super ship...