Is there a word for the category of words that represent alphabet characters? e.g. zee, bee, see, es, etc. This is required for purposes of textual banter.
I don't think there is a word for indicating alphabet letters, specifically; However, such words definitely fall under the onomatopoeia category of words.
: the creation of words that imitate natural sounds*
1: the naming of a thing or action by a vocal imitation of the sound associated with it (as buzz, hiss)
2: the use of words whose sound suggests the sense
— on·o·mato·poe·ic -ˈpē-ik\ or on·o·mato·po·et·ic -pō-ˈe-tik\ adjective — on·o·mato·poe·i·cal·ly -ˈpē-ə-k(ə-)lē\ or on·o·mato·po·et·i·cal·ly -pō-ˈe-ti-k(ə-)lē\ adverb