Hi, it looks like you're using a Synty character, I've recently met this issue when using their assets - some of their characters have some scaling issues for objects underneath their hands, some don't. The best way to handle this is to use parents with object identifiers, which is what you're supposed to do in any case to begin with. Take a look at this character prefab I made :
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As you can see, I set the parent's scale to 100 on all axis for charactes that have this scale issue, and leave it at 1 for other characters. You'll need to check which characters have this issue and manually make this scale change, but it's more annoying than really complicated. Hope this helps !
Edit : Oh and in case you don't know about that, the Object Identifier needs to have the same value as the weapon's Spawn Parent on the related Perspective Item script. You can also take a look at the demo Atlas character and weapons which are good examples.
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