So, regarding the knives I can legally carry concealed fixed blade or folder.
Every assisted opening knife is illegal.
Every double edge blade is illegal.
Every knife with knuckles on it's handle is also illegal.
Double edged knives are considered as a weapon, single edge knives are considered as a tool, but every tool can be used as a weapon. So, regardless of which knife you EDC there are some things to keep in mind. You can't go to mass gatherings, concerts and bars carrying your knife, the same way goes for other tools like a hammer or screwdriver for example. And your behaviour plays bigger role than the type of knife you're carrying.
As a construction worker I carried Recon Tanto on my tool belt next to wire cutter, small hammer, few screwdrivers and pilers. I even walked like that in front of police officers on occasions, and I was never bothered by anyone, same like my coworkers, despite the fact few of us carried fairly large blades. But, I only carried it at work. I never carried that knife anywhere else except the forrest.
My current choice for EDC is very simple - a reasonably sized (small) fixed blade knife. I don't show it off or do anything stupid with it, and I don't carry it on my days off when I'm just going to spend my time with GF or friends in the city.
I did use my EDC knife at work or during other situations in the past, and I never had anyone frown upon it or make comments about it since it's a plain looking normal sized blade.
Norms are different these days, so the best advice is to use what is legal and considered appropriate, and also to use it for appropriate things. Just be reasonable, using a Kukri as your EDC while working in the office will turn some heads even if it's legal, and it'll also possibly make your superiors talk to you about it. I get it that there's way too much overy sensitive snowflakes out there today, but unfortunatley the system will be on their sides in most cases.
It's not worth losing your job, paying fines or spending time locked up because you carried a knife.
Sorry for long post.