Hi Ings! Affixes can be modified by stats. Pretty sure there is an "item level" kind of stat too. You tell the affix to react to a stat using a STATMODIFYNAME line in the affix code. There are other lines which go along with using STATMODIFYNAME too. U can search through the vanilla affixes for examples to reverse-engineer

I don't think there are any examples using ITEM LEVEL specifically as the modifying stat, but there are a lot of vanilla affixes which use this general stat-modifying mechanic.

This is from ARBITER_FROST_WAVE10.DAT in MEDIA\AFFIXES\SKILLS\



This affix actually uses 2 ways to modify its effects.  In the first orange box you can see it's using EFFECT LEVEL - this is the <INTEGER>AFFIXLEVEL: setting you have for your affix in the skill. Basically it says "set the level of this effect by multiplying the affix level from the skill by 6.3829787234".

From here you just need to find the right stat to use for "ITEM LEVEL" and experiment with the multiplier value until you get the affix behaviour that you want.

In the second orange box, the effect gets modified by OWNER LEVEL.  This particular stat doesnt seem to need any multiplier; I think it adjusts the effect level directly.  You might still be able to use it for your weapon affixes though

Hey @Ings ! Since youre after the affix getting ajusted by item level, looks like the second option is what you want.

Did you actually find an affix that uses ITEMLEVEL? Cause like i said ive never seen one (yet) myself and its important that whatever stat you use actually exists If any mod is using, theres a good chance its in "Expanded Skills" mod by @doudley and others. U can try search in there.