A couple of years ago the galaxy was replicated/split into legacy (Horizons 3.8 & console) and live (PC Odyssey and Horizons 4.0), since that point the two galaxies have been completely independent of each other, there's no crossover.
Legacy is in maintenance mode and has not received any software updates since the split. I believe an old AX CG is recreated periodically to allow legacy Cmdrs to reach console achievements.
Live galaxy continues to be updated, and still has CGs (although these have become far less regular than they used to be). That's where the Thargoid War happened, and it's actually had a busy year in terms of feature updates - new ships, engineering and PowerPlay reworks etc. System colonisation is the next new feature due.
If you have the ability to play on PC (or a cloud gaming platform supporting Elite) then Frontier have published a console copy mechanism which will take a copy of your legacy console commander and create it on the live galaxy. Not everything gets copied, so they suggested a process for managing the transfer which is worth reading to avoid disappointment (e.g. selling the FC and waiting for the credit refund, since FCs are not transferred but credits are). It's a one-off copy, so it's worth getting things arranged on console before starting it. It's non-destructive to your console Cmdr, that remains exactly as it was.
