Ideally we should think the other way around, when it comes to implants working as keys.
Traditionally each door will have one lock, and each lock only accepts one key. So you make copies of that one key to give to whomever needs them.
This way, for each new door you gain access, you gain a new key.
Now, thinking within RFID logic, you should flip that:
Each door can have multiple keys, so instead of giving a copy of the key to each person allowed, you should give the ID (key) of each person allowed to your door to handle.
So you should only need one key to have access to as many doors as you want.
What does that mean?
let’s say you have your gym locker, your work badge and your building’s lobby, each one giving you a key card.
In an ideal world, instead of getting 3 implants, one to clone each card, you should have only 1 implant, with your unique ID, and then ask that ID to be entered into the system at your work, at your gym and at your home.
This way you should only need one key.
Why Ideal world?
Because unfortunately technology evolves faster than people can understand it, so most folks are still used to thinking about keys like they used to. So you can find even lock manufacturers who make their locks tied to a single ID, and then you need to clone the card to have multiple users…
Also, there are many different implementations, not only regarding HF and LF… but certain readers (or microcontrollers) are programmed to only read a certain type of card.
So that might make it so you need multiple chips.
Check what are all the cards you actually need to clone, then reach out to the people who manage security there and ask if you could add your chip into the system instead of getting a new badge/fob…