I opened some battletomes and find this "Each IDONETH DEEPKINWIZARD in an IDONETH DEEPKIN army knows an additional spell chosen from the Lore of the Deeps"
"You can choose or roll for one spell from one of the following tables for each SLAANESH WIZARD in a Slaanesh army."
"You can choose or roll for one spell from one of the following tables for each SKAVEN WIZARD in a Skaventide army."
GHB 2019 IJ lore rules:
"You can choose or roll for one spell from one of the following tables for each WIZARD in a Ironjawz army."
Ok. I found this and this in FAQ, so i think we need wait new FAQ first of all because of new Mersenary system
Q: If a warscroll or set of allegiance abilities has a rule that contradicts the core rules, can I use it? For example, Lord Kroak has a rule that allows him to attempt to cast Celestial Deliverance up to three times in the hero phase, but this contradicts the core rule that you can only attempt to cast a spell once per turn. A: Warscrolls and allegiance abilities take precedence over the core rules that appear before the core rules for battleplans, warscrolls and allegiance abilities. This allows you to do things that would not normally be allowed. In the case of Lord Kroak, his rule means he can attempt to cast Celestial Deliverance up to three times in the same turn.
Q: Some spell and prayer allegiance abilities say that can be used by Wizards or Priests in the army. Does this include allied Wizards or Priests? A: No. Allied models cannot use or benefit from allegiance abilities.