How do I summon a named mob?

A space for a name is now included in the /summon command.

Let's look at the documentation for the command, specifically the syntax.

summon <entityType: EntityType> [spawnPos: x y z] [spawnEvent: string] [nameTag: string]
summon <entityType: EntityType> <nameTag: string> [spawnPos: x y z]

So looks like we can type an entity name right into the command! And it looks like we get two options for the command too!

You use the top version if you want to use a spawn event in your /summon command. If you don't want to use a spawn event, you can use the bottom version.

For example, to replicate the JE command in the question:

/summon zombie TheUndead ~ ~ ~

If you want to use a spawn event...

/summon zombie ~ ~ ~ minecraft:as_baby TheUndead

Note though, that if your mob name contains spaces, you must surround the name with double quotes ". If, while doing so, you need to include a double quote as part of the name, escape them with a backslash \ before each one.

/summon zombie "Hello! My name is \"The Undead\"." ~ ~ ~

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