Although I haven't tried it myself, it looks like pass already supports this using the PASSWORD_STORE_KEY variable in the set_gpg_recipients() function. [0]
Initialize new password storage and use gpg-id for encryption. Multiple gpg-ids may be specified, in order to encrypt each password with multiple ids. This command must be run first before a password store can be used. If the specified gpg-id is different from the key used in any existing files, these files will be reencrypted to use the new id. Note that use of gpg-agent(1) is recommended so that the batch decryption does not require as much user intervention. If --path or -p is specified, along with an argument, a specific gpg-id or set of gpg-ids is assigned for that specific sub folder of the password store. If only one gpg-id is given, and it is an empty string, then the current .gpg-id file for the specified sub-folder (or root if unspecified) is removed.
Initialize new password storage and use gpg-id for encryption. Multiple gpg-ids may be specified, in order to encrypt each password with multiple ids. This command must be run first before a password store can be used. If the specified gpg-id is different from the key used in any existing files, these files will be reencrypted to use the new id. Note that use of gpg-agent(1) is recommended so that the batch decryption does not require as much user intervention. If --path or -p is specified, along with an argument, a specific gpg-id or set of gpg-ids is assigned for that specific sub folder of the password store. If only one gpg-id is given, and it is an empty string, then the current .gpg-id file for the specified sub-folder (or root if unspecified) is removed.
-- https://git.zx2c4.com/password-store/about/
EDIT: Better formatting