I have seen a lot of people complaining about how hard it is to play German cruisers. While cruisers in general are a very difficult class to play, especially at high tiers, German cruisers have a very specific niche that must be respected in order to excel with them. However, if you are able to effectively use them, they generally have the HIGHEST potential damage output of any ship in the game.
I am going to go over the specifc play styles needed for cruisers, as well as highlight specific differences between the individual German ships. I am not going to cover the cruisers before the Konigsberg, as they have no similarity at all to the rest of the line.
To start off, I want to emphasize the role that cruisers fill. Some cruisers (Cleveland, Atago, Murmansk, Zao etc.) excel at leading formations, or even engaging enemies by themselves. While German ships can and do easily 1v1 other cruisers, their main role is supporting other cruisers with dps support, specifically at long range. At higher tiers, German AA gets quite good, and can be an adequate fill in for a US cruiser. Starting at the Konigsberg, the German cruisers consistently get better range than their counterparts. Not only is this range effective, but the shell arc improves greatly as well, allowing German cruisers to accurately hit their targets, even out to the very edge of their range. Now this range is very necessary, given that German cruisers also have the weakest armor. Having that range also allows German cruisers to support fire at multiple points, allowing you to cover multiple caps, as well as easily switch to other targets of opportunity. Another thing you should know is that German guns get the best AP shells, with significantly higher damage as well as having usually faster firing rates and faster turning rates than their contemporaries. This comes at the cost of having useful HE shells, which are weak compared to the US and IJN HE shells. HE does not care about angling for the most part, and while doing less alpha damage than AP, applies more consistent damage over time. Thus many people do not like German cruisers as they think HE isnt worth using (which is wrong by the way) and AP relies on dumb opponents.
There are 3 ways to heavily increase your dps and application with german cruisers
1) Focus on staying at mid-long range so that you are not detected. I like to sail in areas where i have a T angle of attack. Usually the best way to do this is engage cruisers that are in pursuit and pushing forward. In my Hipper, I would often easily kill Atagos, by waiting for them to engage in chase on friendlies. When they showed broadside, I would quickly fire a volley, angle myself away, and then fire another before ceasing firing in order to conceal again. Given the high accuracy and velocity of the railgun like German 203s, 2-3 citadels a volley were common. At this point your enemy will likely be either crippled or dead, leaving little chance for return fire.
2) Focus fire on BBs being fired upon by your team. Many people so not know that German AP rounds can easily penetrate battleship belt armor at pretty much any range. You will rarely citadel (although i actually citadel Izumos in my Roon quite often) but the 33% pen damage adds up quickly. This works against both broadside and angled BBs, as German shells are accurate enough to all hit the superstructure. For example, a Konigsberg hitting all 9 shells into a BB will have a volley of around 5-6k, every 7 seconds! It gets even more ridiculous with 203s, where a Roon shooting an Iowa can expect between 7 and 15k a volley, every 10 seconds. Why lament the lack of HE damage and fires, when you can kill BBs with good old pens!
3) Late game, when battleships are spread out and fewer in number, the German cruisers really excel at hunting down and killing DDs. German Hydroacoustic is significantly better than the others with a 5km assured detection over 3.2. Even though your HE is weak, the ability to find DDs in smoke, as well as hit them at distance makes them surprisingly excellent DD killers
I hope I have shown how much damage you can do in a german cruiser, however the key is staying alive. Choosing your turns wisely is key at high tiers, as BBs gain very precise guns. You also need to be weary of torp walls, as German cruisers tend to have large hulls, and slow turning circles.
Now onto the specific ships
Konigsberg/Nurnberg: These ships are very strong for their tier, heavily out dpsing their contemporaries. Furthermore, the light armor and lower ranges at this tier really allow you to shine. With AFT, both ships have a 19.8 km range, and you can actually hit at that range as well. The armor on these ships is noticably weak however, in that engines are lost frequently. Your ideal targets in these ships are Murmansks/Omahas, Furutakas, New Yorks, Clevelands, New Mexicos, and pretty much any Japanese or American DD
Yorck: The yorck is different from the rest of the line, so dont focus on its playstyle very much. It excels probably the most of any ship as a DD hunter, given its HE velocity, hydro, nimble turning radius, and forward firing torps. The AP has a significantly slower velocity than HE however, and so it will not really hit anything past 10-11km. At beginning of games, you need to stay at range, in order to avoid to avoid BBs, but mid game I highly recommend fighting at close range with it. Its AP damage is so strong that it will quickly out dps any other cruisers, while ironically its armor is so weak that, when bum rushing BBs, they will generally overpenetrate you at close range. Ideal targets are the Atlanta, Pensacola, and DD, and the colorado.
Admiral Hipper/Roon/Hindenberg: This is where the line gets even more niche. The damage potential heavily increases, while all ships suddenly becomes much more balanced in terms of power, making survival more difficult. Play intelligently, and pick your targets carefully. Your shells are fast enough to catch cruisers in the middle of a turn, so you need to heavily prioritize, and dont be afraid to switch targets. Your job is to weaken the enemies for your teammates. One great advantage of these ships, is the HUGE health pool you get. This makes the repair ability quite effective. Also the citadel is in a different location on these ships than US and IJN, so while you will get penned often, citadels were much more rare. Ideal targets are pretty much everything but IJN DDs and bow foward Yamatos. BB superstructure gets huge at these tiers, making it trivial to do good damage to them.
Anyways, thats pretty much all for now. Any questions you might have, feel free to comment below. Sorry for the huge wall of text =:O