I had this same issue. Use a shared vault with OTP. Anyone with access to the vault can see the same 2FA code.
As for shared SMS, look into Google Voice. They automatically forward SMS texts to email as an option. I created a "shared" email account and gave my family access to that.
A lot of sites won't allow you to use a Google Voice number for your 2FA. There are services now that will validate if a number is VOIP, and then the site you're on can choose to filter those at the application level.
I did find a way around this, in that I had a real number, added all my 2FA accounts to it, and then ported the number to Google Voice, but this isn't a long term solution. Idk how long Google Voice will stick around, but I have found a couple backup options that are low cost if I need to keep the number long term.
But the shared accounts that are my pain point only offer SMS OTP.