I wouldn't consider an Irish B/C or B/C/C# as chromatic. I think they're still diatonic, though you can get the total chromatic scale by going across rows.

I think chromatic TENDS to mean that it has all the notes of the chromatic scale when pushing in the same direction, and that notes on the pull are the same note as on the push.

I also think this is somewhat of a grey area, but leans heaving to what I just recounted.

A piano accordion is chromatic. A 3 or 5 row chromatic is chromatic.

This all is very interesting and i didn't know anything about all those different systems. Am I right if I say that each row on a Irish have a diatonic scale, but together with the other row you have chromatic possibiities?

Yes, that would be right.

CBA or Chromatic Button accordeons are also known as Continental Chromatics.
They come in "B" systems or "C" systems. also known as B Griff or C Griff.
They are usually 4 row or 5 row.. I have seen 6 rows but these were the Russian versions known as BAYAN.

These are not diatonic.

If I were starting accordeon all over..I would start,and stay with a CBA.