I have a reliable source that has informed me that we will be getting two future updates to Pokemon Sw/Sh. They will be free downloads and they add previously unavailabe Pokemon and characters to the game. The first update will be released in late February and will bring back all the starters from previous gens as well as a few other Pokemon including Weedle, Ekans, Seel, Aipom, Houndour, Cacnea, Clamperl, Buizel, Sewaddle, Alomomola, Flabebe and Yungoos. All these Pokemon will be available to catch in event raids and added into Dynamax Adventures. The update also adds the opposite games gym leaders, Honey and the opposite Isle of Armour Rival as available partners in The Galar Star tournament.
The Second update will be due in the middle of the year and it adds all previous unavaliable pokemon as well as Red and Blue in the Star Tournament. There are also mythical events planned to start in each month of next year starting with Diancie in January