Interesting possibility - what if the HSF gets orders to sail and the later mutiny happens? The crews know it’s a suicide mission and the breakdown in discipline didn’t happen overnight...
I don't know that it changes that much really. There will be some court martial of a few sailors, but I just don't see any big impacts. It will scare the German leadership, but lets assume the Kaiser decides to "really take the gloves off on land". What additional steps can the Kaiser or his military leaders do? The war ended because the Germans ran out of infantry reserves. The only other possible available reserves are the A-H empire. They sent a full army IOTL that was in the line against France. Maybe there is another available and they Austrians can be persuaded to use it? Maybe there are a few Turkish corps that might be available. And maybe the Germans could attack with a half dozen or so extra corps. And maybe they accidentally take a critical objective.
So just step back a bit. It is January 1918, and we have a time machine. You and I go back in time to help the Germans by changing strategy only. What do we do to win the war? Or to get a good peace deal? We easily help the Germans do better by doing things such as having clear military objectives in their Spring Offensive. We can probably help them be a little more efficient with the food issue, but we will have to end up doing things that will be seen as immoral such as run the 1941 Hunger Plan in 1918. I guess we could simply strip 100% of the food out of Poland, for example. But does any of that win us the war? To the navy, we can probably get a few more U-boats and torpedo boats out of ship yards. We can not worry about losses since we know that everything gets lost at the end of the war anyway. We can certainly find a bit better way to sink ships. But what can we do to win the war?
The best plan that I can come up with to use the surface ships to win the war is not to suicide the channel. It is to try to make the British think I am going to run the Dover blockade, and maybe, just maybe the British will suspend merchant traffic. We could do a covering sortie with the main fleet, and use it to run the battlecruisers and faster battleships to Ostend along with all the cruisers. If I have credible fire power that is just a few hours from the Dover blockade, maybe the UK will panic and suspend merchant shipping. But i really doubt this one. The UK lost 2 BB in a single day to a single sub near Gallipoli, and AFAIK, it had no impact on the supply pattern to land forces.
The only other idea that I can give you is crazy. You assign two corps to the German coast line. You assemble enough merchants ships to carry all these troops. Under the cover of darkness, you rail out these corps to attack in Flanders. That next morning, all the merchant ships leave in convoy towards the Eastern Coast of England. These ships will be empty except for merchant seamen. The HSF sails to cover. Maybe I don't even tell the admiral in charge that the merchant ships are empty. The UK would be forced to react with everything it had. But the problem with this ATL is that I am relying on knowledge the Germans don't have, at least not widely enough. I am counting on the British being able to see me assemble the land units with spies and pickup the naval intercepts. And then the British keeping a dozen or more extra division in England, not Flanders.