No. It's kind of pointless really, it's much easier to just import one.
Can we import an address into a bip32 seed? I dont think thats possible.
No you can't import it "into the seed", you can import it into the wallet itself, electrum allows this. So if you restore your wallet from seed you will lose the vanity address unless you have the wallet file.
Also it will be very easy to generate the public from the MPK but say you found an address you like and you keep the "index" You will have to regenerate all private key prior to that index if all you backup is the seed and the index.
lol in a way that is a nice spend preventer since you can receive bitcoins easily to that address but it would be hard to use the backup to spend.
kinda nice to force yourself to not spend unless you have the dedication for it