The 5e Wish spell does, literally, whatever you wish, but for a price. The Basic Use version may be useful for instant spell research without the usual time / gold costs. Logically, one could use this Basic Wish to learn all the wizard spells lvl. 8 and lower. But what are the limits? To quote:
The basic use of this spell is to duplicate any other spell of 8th level or lower. You don’t need to meet any requirements in that spell, including costly Components. The spell simply takes effect.
Here are some possibilities:
Casting ‘Wish’ may allow one to have a version of any existing / official spell (found in Player’s Handbook, Volo’s &/or Mordenkainen’s manuals). This exists as a memorized spell ‘slot’, uncast, in one’s mind. Wizards (class) could then write-scribe this spell, providing this was a wizard’s (spell-list) spell in the first place. This learning technique may also extend to some ritual spells, q.v.
As the Basic Use of a ‘Wish’ spell does NOT require material components. As such, the caster of this spell can automatically gain one (1) fully transcribed non-magical version in a book (or scroll / carved tablet / scribed on a skull / whatever suits your fancy). Should this be a ‘wizard’ spell, the caster could then use this written version as though they had transcribed this themselves. Other wizards would need to endure the usual transcription-study-cost process from this origin material, as normal.
This Basic Version of the spell vetoes any and all requirements! As such, any spell imaginable (of less than 8th level value) can be instantly scribed into a book. If it were considered a ‘wizard’ type spell others of that class could make use / transcribe it as usual. If it were a spell for any other list, those of the appropriate class could use this written spell to re-establish a new relationship with their deity, patron or other spell-delivery creature.
Off the cuff, the first one seems reasonable. The second version seems to be pushing boundaries a little (not sure why). The last one, drafting out Brand New Spells every day, seems totally implausible for a mere Basic Wish (perhaps a FULL wish could do this?) – yet i have no known RAW defence on this. It just seems like a bad idea to let a CR 11 ‘arch-mage’ pump out 300+ spells (of any class / up to 8th lvl) in any given year, risk free. But… why not?
Gathered Exchangers of Stackings… what say ye?