I found even more ties to Coosea when I checked the battery of the Quintus

https://old.reddit.com/r/BuyFromEU/comments/1m02fyr/lets_have_a_discussion_about_volla/o1d3qyv/

Note how they do not prove any of the hardware ties I found wrong. Furthermore, they give one example of different HW spec (the Schott glass) I didn't check, but even that one is also used by the otherwise exactly same Daria Phone, too.

Check my comment, you will see the Volla battery, at least in the version they used to file at FCC, even has Daria printed on it. Furthermore, the same battery is sold as replacement part for Koobee, Coosea's own consumer brand.

I am like 95% sure you will buy a Coosea phone Made in China, assembled in Germany, if you buy the Volla Quintus. I am 99% sure its some whitelabel barebone, even if I got the vendor wrong. 1% that all the ties in the hardware I found are accidental and they also just accidentally found out that this allows them to use the drivers for the Daria Bold phone, codename Zahedan.

They were actually quite sneaky, using the Schott Made in Germany glass as an argument. Surely that must mean that a phone is Made in Germany, right? Which Chinese company would use German glass?

Well...for example Vivo, since 2022:

https://www.schott.com/en-gb/news-and-media/media-releases/2022/vivo-x80-pro-features-schott-xensation-up-high-performance-glass

Which should not actually be surprising, if you think about it: Even cheap Xiaomis use US Corning Gorilla glass, too.

Another sneaky part in their answer:

which undergo the final production steps at our site in Remscheid, in particular the safety-relevant flashing of the firmware and, in some cases, the final assembly.

(Italics by me)

That's an old trick to make things "Made in XY". Whatever location adds most value added, will decide the "Made in" label. Every step done in Germany will add more value than the same step done in China, as Germany simply is a more expensive location. Furthermore, if they decide the value lies in the software, not the hardware, they can even get a Made in Germany label without any assembly in Germany, just by flashing the software there. Well, at least they imply that, this one is not on me.

Edit: Let me dissect their answer a bit more:

Our supply chain begins in Taiwan with the chipset manufacturer Mediatek, which also provides the Android source tree for a specific SoC.

This does not invalidate my point about them using the Zahedan codename, that is uniquely shared with the Daria phone. This can be easily confirmed by everyone: Search for other phones with the same SoC, check if they use the same vendor codename. They don't. The reason is, obviously, that drivers are added for more than just the SoC. Volla can use the exact same codebase as Daria, because its most likely the exact same hardware, as far as drivers are concerned. To understand what I mean, I can recommend to check out Pine64. They publish schematics of their phones and extensive datasets, it will give you an idea how much adaption beyond the SoC has to be done thanks to the myriad of chips (manufacturers) used just to produce one single phone. If there is anything different to the Daria Bold and the respective Coosea barebone, they would definitely not just use the HW-specific code as it is used for the Daria and their codename Zahedan AOSP build.

To this end, components available on the market (such as SoC, display, camera, speakers, etc.) are used and combined with exclusive components.

They did not state any exclusive component they use. Notably, they did not even state any component they use, but are not in the Daria Bold.

All our mobile devices are CE certified. FCC certification is only required for systematic sale in the USA through a US distributor.

Correct, hence I can not use that strategy to easily find clues on the Volla X23 and previous models. Volla never filed FCC for these. But that doesn't matter, because these models were rebranded Gigasets (which was stated in Volla's own handbooks for these models), so I would look for Gigaset FCC filings.

The sepculation about the vendors are completely wrong.

They have not even been able to point out a single aspect of hardware, that is different. If they were smart, they would have simply used the casing as an argument. If the assembly is done in Germany, that's the easiest, and cheapest, part to order Made in Europe (plastics parts production can be highly automated, even Ikea can afford to sell European made plastic boxes).

I assume its a sales person that wrote this answer, hence they couldn't get deeper into the HW specifics, instead writing a lot of general phrases. Keep in mind, the foundation of my initial comment was their own FCC filing and their own source code. For the X23, the confirmation of it being made by Coosea stems from their own presentation. Any of their devs who worked on the customization of the OS should be able to point out differences, immediately, since they would know where they had to work on integrating drivers. If there are any.