Getting correct shade/brand of concealer?

I spent about an hour with a counter gal so got the shade of foundation just fine.

There being so many foundation shades I knew that was gonna take time.

Concealer however, I figured shades were "light/medium/heavy".

Easy, go for medium.
Turned out to be too light.
Went back got something darker, "nude 2" in a different brand, turned out to be totally off colour.

Initial concealer was also insufficient coverage and very liquid.

20 euro, not the end of the world (anyone wants to do a trade I'm open)

.....

Do I basically have to wait until we come out of lockdown so I can sample a bunch of swatches to get the right colour and coverage?

Maybelline eraser was the 2nd brand - better coverage, impossible shade.

Are there any recommended concealers specifically or is it just, try them all?

**
I started using makeup relatively recently and as a dude, must say I'm thrilled with results.

I've learned to blend it very well for full discretion, with a precise straight razor shave and contoured eyebrows - some eyebrow gel - dramatic improvement.

Getting the concealer correct is the last hurdle to cross - the last point I'm simply not satisfied with.