The two scripts have a one-to-one glyph correspondence, so the work the same. Each is sort of an abjad, sort of an abugida, sort of a syllabary, sort of an alphabet. The only types it is missing is logogram and abjad, but we can’t even be sure of that because the underlying language of the scripts is poorly understood. (They are pretty sure about the correspondence of glyphs to pronunciation by correlating names in Meroitic script with those in other scripts.)
Like Old Persian, consonantal glyphs have an implied vowel “a”. With a vowel following it, the syllable changes to use that vowel in it, sort of like an abugida — if you say that a following vowel “decorates” the consonant. However, the “e” glyph seemed to be a “killer mark”, to signify that that syllable wasn’t a syllable, just a consonant. (This is similar to the Virama in Brahmi-derived abugidas.) However, it’s not even a true killer: sometimes it would also be pronounced as an “uh” (schwa) sound. They think.
In addition, there are four glyphs that are never followed by another letter. They think that these were syllables that ended in “e” (an “eh”-sounding “e”, not a schwa-sounding “e”). They think.
There are some writing systems that I am biased towards. I think that Cree, Cherokee, Greek, and whichever came first of Brahmi and Kharosthi were brilliant. Then there are some writing systems where I roll my eyes and ask, “What were you thinking???” Meroitic joins Old Persian, Pahlavi, and Aztec in that category for me. I have less patience for Pahlavi and Meroitic because they should have known better, from the examples of Greek on one side and Brahmi on the other.
About the only thing they did right IMHO was separate their words with either two or three vertical dots (like colons).