Can you use the Transmuted Spell option from the Metamagic Adept feat on spells with a duration?

Question

For example: let's say that at 3rd level a Druid grabbed the Flame Blade spell and at 4th took the Metamagic Adept feat, choosing Transmuted Spell as one of their options.

The description of Flame Blade says:

You can use your action to make a melee spell attack with the fiery blade. On a hit, the target takes 3d6 fire damage.

The Transmuted Spell description says:

When you cast a spell that deals a type of damage from the following list, you can spend 1 sorcery point to change that damage type to one of the other listed types: acid, cold, fire, lightning, poison, thunder

Does this mean that when they cast Flame Blade, or any other elemental spell with a duration, does Transmuted Spell apply to all damage done by the spell over the course of the full duration?

Answer 1

Yes

Flame Blade is a spell that deals fire damage. You can change the type of damage spending a sorcery point when you cast it. It will then deal damage of the changed type. There is no text that would limit the effect to only spell attack spells, or instantaneous spells, all that is required is that the spell is able to deal damage of one of the types on the list. It works on all such spells.