With the latest live stream, it is confirmed that Industrial Zones (IZ) still have their standard (+1) adjacency bonus for mines and quarries.
In the case the Hansa still get its bonus from Commcerial Hubs (CH) and ressources, it shows that Germany might have weaker IZs in the matter of raw production power than other civs.
So the Hansa is not that powerfull and would maybe as an UD with the same boni for Germany imbalanced. But the fact that Germany can construct it in any city without looking for the district limit is still the strong side (plus in half the time).
Germany will probably have all/a lot of their cities very strong in production compared to other civs. It can get further boosted if most of it cities will use their additional district for commercial hubs to push further the production outcome and get additional gold income which is always usefull.
So Germany's City will be likely stronger in production and gold in general average then the cities of other civs.
To beat Germany in production you have to focus on specializing to found a lot of production focused cities with all it pros and cons. Most likely this will only do civs focused on military/aggressive expansion. In the moment the Aztec, Japan and Scythia are most likely to do it.
But at the moment I think the true production monsters will be the Japanese if they can hold their stand until IZs and of course Electronic Factories (EF) are available. With the Meji Restoration Japan will be more likely to get their +6

IZs. And until now it was only mentioned that Japan's EFs will give boni to other cities not just their home city.
If you manage to get 2-4 IZs close together and build in every one an EF, Japan will go sky rocket in terms of production. It doesnt have a late game UU this time, but it will be in the lead of production and can pump units like crazy.
Not considering the fact that it will get a culture boost and therefor it might rush the civic tree and unlocking Corps and Armies. So Japan will be able to mobilize an huge army very quickly later in the game.
And giving the fact how powerfull coastal raiding can be (yeah, I think there might be at least on coastal raider unit for everyone) the Divine Wind ability helps greatly to defend your shore.
But in generall, it is hard to tell which civ is really the strongest. Too many open questions. But maybe the OP should be added to make a comparative basis. And I think the general opinion is that the standard is "Continent Map, Size Standard, Game Speed Standard". At least that is the configuration where all Civs are best to compare to each other. Alone the fact that there are now more naval UU shows the intention of Firaxis to give the seas more importance then before.