There is no function in the game to "remove a spell from a hero." All spells are given to a hero permanently.
Therefore, we decided that all new artifacts that grant spells to a hero should be "Ancient Relics."
And all "Ancient Relics" are given as non-transferable, and the effect of granting a spell is "Passive."
This is the only way to make it so that it doesn't look like a workaround and the system works uniformly, without any unnecessary nuances.
There is already one such artifact in the test version. It is very... Special. And to collect it, you will even have to complete a "mini-quest" (we are waiting for the first person to find this artifact :D)
Don't confuse them. Scripts are scripts, and effects from standard artifacts are something completely different. There is currently no way to link these effects to other artifacts.
I understand that many of you may not know what can be done and what cannot. I am saying all this only so that you are not surprised why some good ideas will not be implemented.