As far as I'm aware, you can still transfer from Bank to Home as long as you have the app downloaded on your 3DS (since the servers aren't shut down yet as mentioned by Cdijk16).
According to a Reddit comment: "you apparently can use the eShop to install Bank and Transfer if the account associated with your 3DS has ever opened those apps (essentially you can redownload them as long as you previously had them on your system)."
If you don't have Bank, I *think* you can download it by modding your system? I have no experience to say if that's true or not.
However, if you don't have Pokemon Bank on one 3DS but you have another device that does (be it your own or someone else's), you can transfer Pokemon from your cartridge to that devices Bank, and then transfer to your own Home.
If none of those are any option, I think you're unfortunately out of luck.