Some magical items, such as scrolls, work only if a given spell is on the caster’s spell list. For example:
A spell scroll bears the words of a single spell, written in a mystical cipher. If the spell is on your class’s spell list, you can read the scroll and cast its spell without providing any Material Components. Otherwise, the scroll is unintelligible.
The Aberrant Mind Sorcerer and Clockwork Soul Sorcerer have access to additional spells not on the Sorcerer’s spell list:
You learn additional spells when you reach certain levels in this class, as shown on the Psionic [Clockwork] Spells table. Each of these spells counts as a sorcerer spell for you, but it doesn’t count against the number of sorcerer spells you know.
Additionally, it is possible to swap these spells at level up:
Whenever you gain a sorcerer level, you can replace one spell you gained from this feature with
another spell of the same level. The new spell must be a divination or an enchantment [abjuration or a transmutation] spell from the sorcerer, warlock, or wizard spell list.
Do the additional spells from the Psionic/Clockwork spell tables count as being on the Aberrant Mind / Clockwork Soul sorcerer’s spell list?
What about the spells that can be obtained by swapping the Psionic/Clockwork spells out?