Why is my Keychron K5 keyboard not recognized on macOS Sequoia?

Apple has system settings that should let you fix that. Search for “modifier keys” in the settings app.

The Keychron itself probably also has a way to switch these the way you want them.

Change the behavior of the modifier keys on Mac - Apple Support

James-Ahh wrote:

Oh so this is by design?

There is only single layout for each language that Apple supports and not possible to find or replace fixed layouts other than getting third party software like you suggested?

Apple often provides multiple layouts for languages -- there are 3 for Finnish:

Unfortunately they all have \ on option shift 7 instead of where you want it.

There are 7 layouts for French, including one for Windows users.

It's really simple to use Ukulele to create custom layouts for the Mac, I made dozens of them myself for people who need something different, and there are lots of ready made ones that you can just download and install.

Unfortunately I have not seen one for Finnish PC yet. If you detail the changes you need, I could make one up in very little time and post it.

If it’s just the left corner keys, sounds like a keyboard type problem. See

How To Fix Keyboard Type Problems - Apple Community

James-Ahh wrote:

Multiple keys do not match.

Could you provide specifics about those non-corner keys that produce something other than what the Finnish-Swedish layout picture below shows them producing? Do you have the Finnish icon showing in the top right of the screen as shown here?

James-Ahh wrote:

Backslash is only found at shift+option+7 when it should be option+?.

That sounds like you are used to the Windows Finnish layout. Apple's layout is different. To put \ on option ? and make other changes like that, you can create a custom layout with Ukelele.

https://software.sil.org/ukelele/

It's possible someone has already done this, but I have not seen one on the web.