wtf are avenger and musashi? i guess they must specific classes to the game boy "version" of the Wiz Empire series; although the sixtuplet of 'Empire Wiz games are all made by same devs: Starfish studios.
The following assumptions i'll type below this sentence will be predicated on the simple and logical conclusion that: Starfish kept spell schools and classes the same, or "pretty much the same". I know, for example, the 3 Empire Wiz games on GB/GBC feature the same Races as the 3 Empire Wiz games on PC/PSP.
So, having said that...
Kunoichi normally get access to Alchemi spells in the Wizardry Empire series on PC/PSP/PS1; and since this is from same devs, in the console Empire series there is a martial class called "BERSERKER", which MIGHT be the same thing as the "Avenger" you are talking about.
MIGHT be. To me... it makes sense. Same devs, same series, similar sounding names. Anyway, the BERSERKER class in Empire series on consoles/PC get access to special-Berserker spells, i think they get 4 of them. More like attack moves really than spells.
Mage and Cleric spells are all named the same in all variations of Wizardry so that list you are using (i've referenced it myself) is all you will need for those two spell schools.
The Psionics and Alchemy spell schools, AND also the Summoner class and their "Contract/Summon" spells, were added simultaenously to the Wiz GAIDEN series of games (3 on GB/GBC, 1 on SNES, 1 on PS1, and 2 on PS2 as of 2017), AAAND also added to the Wiz EMPIRE series of games (3 on GB/GBC, 2 on PC and the 3rd one on PSP/PS2 exclusively).
I haven't played most of the GAIDEN Wiz games, but from what I have played (Gaiden 4 and Gaiden 6, respectively), it seems apparent that both GAIDEN + EMPIRE series kept the naming conventions the same, or as close as possible to the same, for the PSIONICS/Alchemy spell schools.
So, I'm saying in a long-winded fashion: I'm certain you can simply use the names of the spells for the PSI/ALC schools in this GAIDEN game you're working on; i.e. take the namings from the PC Empire Wiz games, Emp 1 and Emp 2.
(Just go straight to Emp 2, the one Richard translated, no need to check both). Of course, the 3rd counts too, but it's not translated into english, so the spells are all romaji nonsense.
Summoner gets, again (in console/PC series version of Wiz Empire games): summoners get access to 3 of the 4 spell schools; they get Cleric spells, Mage spells, and Psionic spells. Obviously they also get the 4th "school", which is being able to cast a "Summoning" spell and being able to cast a "Contract" spell.
EDIT: So, I'm almost sure "Avenger" has to be a class equivalent to the console Empire Wiz series' "Berserker" class, or if not the same then similar; but no idea what Musashi class must be: obviously it is probably the highest-tier class for Samurais to upgrade to. I mean, what else would it be?
Traditionally Sammies get access to MAGE spells, so stands to reason Musashi do as well. Mage/Cleric spell names are set in stone and don't change for any reason, so you'll have no problem naming those.