You're required to taste טעם מצה. If flavor of the ink is undetectable, it will not compromise טעם מצה and should not be a problem, but I'd hold off, nonetheless:
Is Egg Matzah Kosher For Passover?
The matzah used at the Seder must be made of only flour and water.
This is because the Torah (Deuteronomy 16:3) refers to this matzah as
lechem oni, which can be translated as “poor bread.” As you point out,
matzah made with juice or eggs is much tastier, and is by definition
“rich bread.” So egg matzah is out for fulfilling the mitzvah of
eating matzah at the Seder.
IMO there's a good case to be made that such matzah is not lechem oni, due to the added ingredients, or perhaps even because of the monogram itself.
See the discussion about salt and טעם מצה and in the comments below.
Regarding when the writing was applied, @user6591 is correct to be concerned. See more there:
But is it kosher for consumption during the rest of the holiday?
On Passover we are forbidden to eat chametz. Now, what constitutes
chametz? A mixture of flour and water that has leavened, whether
through the addition of yeast or the passage of time (18 minutes).
However, flour mixed with other liquids, such as fruit juice, oil,
wine or eggs, does not constitute chametz.
So far, it would seem that there would be no problem whatsoever with
eating egg (or juice) matzah.
However, there is a caveat: If the flour was mixed with both water and
any of those other liquids, it can become chametz. Not only that, it
actually becomes chametz at a much faster pace than an ordinary flour
and water. Because of this concern, it is forbidden to make matzah for
Passover with a mixture of water and other liquids.
Another potential issue here would be erasing the letters on Yom Tov while you eat the מצה. Here's an interesting discussion of the issue: The Melacha of Erasing on Shabbat
He cites the MB there that concludes it's OK:
..Mishna Berurah 340:17, permits one to eat a cookie that has letters
written on it based on the fact that it is a pesik reishei d'lo nicha
lei whose result is only a rabbinic violation and it is performed in
an irregular manner (see Sha'ar HaTziyun 340:22).
There is also this in O-Hach, 460-4:
We do not make designs, like drawing the shape of an animal or a bird
on the matzo. However, everything done with the comb so that it
doesn't swell is permitted, as is putting holes in the matzos.
That seems to apply when baking the matza, because the designs could cause it not to bake properly. This again raises @user6591's question about when the ink is applied.
