And six months later, for the exact reasons in the post directly above yours by me, the answer is still 99.9% going to be “no”.
Quoting the most relevant part:
Class leveling is the longest grind in the game, by far, currently.
Similar to pets, the class shop offers players the opportunity to trade gems for class xp. Rarer than pet shops, because there are 34 classes (by mid-April), each class shop can only appear on the that Kingdom’s event week Thursday once or twice at most per real-life calendar year. This mechanic fits in perfectly with the shop behaviors with other events, to create “now-or-never” buying opportunities, FOMO, etc. There’s no reason for the devs to change the behavior, given the game’s current operating model.
Now, to be fair, on the incredibly small chance that some future new content requires players to mandatory need max-level classes (not to level Power for stars), orbs of growth could be used in the manner you desire. But, and a big BUT, the game is already flooded with them. That would mean each orb would need to be worth a very small amount of CXP to not trivialize the shop.
I’ve played with some numbers this morning on what I would be comfortable asking the devs if I were to make such a request to be anything in the ballpark of being reasonable. Long story short, I can’t rationalize minor growth orbs being worth anything more than a flat 5 CXP, and majors being worth a flat 50 CXP. Yes, a major green orb is 20x a minor green orb, but there’s literally no way they will ever be worth 100 CXP, given that translates to 100+ Gems in the class shop and that a major green orb is guaranteed every single week trivially in any guild event. Plus, there’s the “Treasure Map” problem with major green orbs. The only way I can see major green orbs being converted to CXP at 100 CXP ever being greenlighted is if there was a hard one-per-week (not per class) maximum hardcoded into the system to avoid trivializing the class shop.
TL;DR 6 months later, I still see all-but-zero chances of this happening. Maybe in some very future update for powercreep reasons at very low (possibly time restricted) conversion rates.