Is there a paint(spray)/lacquer for applying on a fretboard?

[stan]

Here is another option:
Use whatever means to ebonize the fretboard you like - ink, another technique, whatever. Do what you need to do to make it black.
There should be little need to mask the frets - as most substances will find it difficult;t to permanently stick to the metal of the frets - and even less so if you polish them first. A very fine grade sandpaper should remove most traces of any substance on the frets - mask and polish as you would if doing a fret dress.
Simply replace the fret dots with polished black plastic. Many older guitars had plastic fret dots and they worked fine...
This would give you a matte black fretboard and gloss black dots.

[Kick]

Here is another option:
Use whatever means to ebonize the fretboard you like - ink, another technique, whatever. Do what you need to do to make it black.
There should be little need to mask the frets - as most substances will find it difficult;t to permanently stick to the metal of the frets - and even less so if you polish them first. A very fine grade sandpaper should remove most traces of any substance on the frets - mask and polish as you would if doing a fret dress.
Simply replace the fret dots with polished black plastic. Many older guitars had plastic fret dots and they worked fine...
This would give you a matte black fretboard and gloss black dots.

But I want a matte fretboard except for the fretboard between the 2nd and 3th fret, the 4th and the 5th, 6th and 7th and so on. These area's on the fretboard must be gloss black (and no dotmarkers).

[stan]

But I want a matte fretboard except for the fretboard between the 2nd and 3th fret, the 4th and the 5th, 6th and 7th and so on. These area's on the fretboard must be gloss black (and no dotmarkers).

Ahh, sorry, reread this...
You could put in big block markers that take up the whole section.... tricky idea, good luck