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GiftedEquipmentPriority

Equipment that's gifted to a character is prioritized and they'll not try to swap it out.
Also includes throwing/ranged weapons, you can gift throwing/ranged weapons with AcceptMoreGifts https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3393596869
Please see the notes on that mod as well.
Gifting a throwing weapon will block a ranged weapon from being automatically picked up and vice versa.

Note that if the character has multiple slots for the same type of gear, like rings for example, in the base game the character only replaces the first slot and the other slots are filled as things are available, never changing and with no regard for quality (the best item is picked at the time that the slot is empty).
This mod ends up replicating the behavior because changing that drastically would involve too much code rewrite for now, when you gift an equipment and it's the first slot of its type it also blocks any other slots from being swapped by the character automatically as it wants, but like in the base game, the remaining slots will still be filled automatically.
If you want the character to have a slot that's possible to be rotated as they see fit, you should give them a non-gifted item for the first slot and for the remaining slots it effectively doesn't matter if they are gifted or not as the game doesn't even try to replace them (but eventually if this logic changes this mod will prevent gifted items from being swapped).

Includes options for controlling behavior with weapons, as characters actually have a main and secondary hand, you can toggle for characters to not pick up any more weapons or shields if they already have one, forcing them into a two-handed style and letting you control their secondary hand manually (you can set it so any weapon/shield that ends up in their inventory are automatically equipped or for them to only equip another weapon/shield if you gift it to them).

Settings can be adjusted in the config file that appears on Elin\BepInEx\config after the first launch of the game with the mod enabled or by using https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3379819704 (allows changing the settings without restarting the game).