Mixins and mixintos with mixintypes

Is it possible to have a mixin in a file that you’re then using your manifest to mixinto another mod’s file and override/remove anything in the other mod’s file? It seems like when I try doing it, the mixintype stuff doesn’t get applied, and I’m thinking that it gets applied and then removed on the first mixin—the mixin specified within that json file itself—and then is no longer there to get applied when the manifest mixes it into the other mod’s file.

I’ll try to give a specific example to explain:

I want my bronze_sword.json to be mixed into the base game’s bronze_sword.json, with one or two mixintypes overrides. However, my bronze_sword.json specifies a mixin of my weapon.json. It seems like the mixintypes get “consumed” on that initial mixin and aren’t around when the manifest mixes the result into the base game JSON. I tried specifying the base game JSON as one of the mixins and then making it an override in the manifest instead of a mixinto, and that just instantly crashes the game.

I also tried abstracting it one level: I made a bronze_sword_mixin.json file that only contained "mixins" of both my weapon.json and bronze_sword.json and then specified "type": "entity", and had the manifest use that as the mixinto for the base game bronze_sword.json; that had the same failed mixintypes result as the original strategy.