>>39413467You will be able to move ALL of them into POKÉMON HOME (see it as smartphone version of Bank) it will act as a bank and will apparently include stuff like trading. They would like to make HOME compatible with main games but also spinoffs.
You will be able to USE your mons in S&S IF and only IF they are in the game. We don't have an exact list of who made it or not.
HOME has been stated to be the main node for everything pokemon in a near future.