How does the Magic Seal effect work, and can I make it player accessible?

So I’ve been hacking FE7, right? Strange thing to hear, seeing as I almost exclusively work on Kaga FEs, but Kishuna is one of my favorite characters in the series, following his departure from IS.
I’ve been trying to find an interesting way to make him a playable character within FE7, but so far, I haven’t had any luck giving him a more unique role than just “worse Athos”.

One thing I would love to do is have him make use of that magic-sealing property of his, though maybe to a lesser extent. The issue, as you can probably imagine, is that magic sealing effects are enemy-exclusive, for whatever reason.
Does anyone know why this is, and is there is a potential workaround?
And if there isn’t one, perhaps someone could suggest something else unique that he could do? I tried giving him a weapon that induces silence on hit, but that doesn’t work in FE7 apparently.

Silence on hit allows for counter attacks. So make it an uncounterable weapon. Easiest solution imo

The issue is that silence does not trigger on hit.

If silence weapons don’t work then you’ll need to write some asm. Status inflicting weapons would be a good first project

There is a bug where enemy AI cannot recognize magic seal if str mag split or melee range fix is installed.
This is the same in FE7 and FE8.
It has been reported that it is determined that melee weapons can be used to attack, and as a result, the enemy will select magic and freeze.
If you want magic seal to appear, you should not give magic to the enemy.

What I’m getting from this is that modifications to the stat system make it impossible for the effect to work, and regardless of patches, enemies will target you with magic, even if it can’t function, which causes a game freeze.
That is… unfortunate.