Does anyone know the name of this algae pattern?

Maybe someone recognizes it from the picture.

Nah, probably not. Since it could be laminate, vinyl, etc. It would have made more sense for you to have researched the source of the picture. And honestly... this kind of design is now available from many providers.

you should have researched the source of the image

Of course, I have already tried that.

this kind of design is now available from many suppliers

I found some that are similar to the picture, but either they are too light or too dark. The one that was the closest is called "Laminat Highland Eiche titan D4796 Mammut plus Landhausdiele," but it has many more and larger veins, so it looks very busy. If you can name me another laminate with this pattern, I would be very very grateful.

You must be looking for a needle in a haystack; the identical product photographed 20cm away looks different again. If you look through the individual manufacturers in the specialist market, you will surely find something soon. You really see something like that more often. Where is the source of the image?

Google image search for "Eiche grau".. you'll surely find something..

Go to a few stores. In the photos, the plastic floor looks different anyway than in real life.

The OP does not seem to be aware that wood is a natural product that does not grow in a reproducible design, and that customers see this more as a feature than a bug. For this reason, manufacturers of imitation decors also make an effort to scan sufficiently large templates and process them in such a way that the effect of natural product authenticity is precisely not disturbed by patterns unintentionally (or even regularly with a repeat xy) recurring during installation. It would be more sensible for the OP to clarify which properties the desired product should have, e.g., "fewer and smaller knots than laminate Highland Oak titan D4796 Mammut plus plank." This then allows the construction-related advantage of imitation products to be used, such as being able to produce "beech texture oak-colored."