Feel free to corect me ... but as i understand it, from warious topics about scrolls and mages learning from those scrolls ... right now scrolls are buged (or not done w/e) since every class can use scrolls just to expand his spell slots ...
Cleric can only use scrolls with cleric spells.
Wizzard can only use scrolls with wizards spells.
Meaning there is not much point in creating scrolls ... especialy if creating one will (expect other reagents) consume related spell slot to add required magic.
Since those character who can use them usualy allready have them in spellbook. :-/
You can copy existing scrolls right now
And do you mean in BG3 or tabletop?