Considering the class feature Tools Required:

You must have a spellcasting focus—specifically thieves’ tools or some kind of artisan’s tool—in hand when you cast any spell with this Spellcasting feature (meaning the spell has an “M” component when you cast it).

and the complete guidance regarding components in the SAC, but mainly:

If a spell’s material components are consumed, can a spellcasting focus still be used in place of the consumed component? No. A spellcasting focus can be used in place of a material component only if that component has no cost noted in the spell’s description and if that component isn’t consumed.

What spells on the Artificer Spell List, TCoE, require the second class level or higher Artificer to have a free hand when they have access to an infused shield or weapon in one of their hands?

Considering the class feature Tools Required:

You must have a spellcasting focus—specifically thieves’ tools or some kind of artisan’s tool—in hand when you cast any spell with this Spellcasting feature (meaning the spell has an “M” component when you cast it). [..] After you gain the Infuse Item feature at 2nd level, you can also use any item bearing one of your infusions as a spellcasting focus.

and the complete guidance regarding components in the SAC, but mainly:

If a spell’s material components are consumed, can a spellcasting focus still be used in place of the consumed component? No. A spellcasting focus can be used in place of a material component only if that component has no cost noted in the spell’s description and if that component isn’t consumed.

What spells on the Artificer Spell List, TCoE, require the second class level or higher Artificer to have a free hand when they have access to an infused shield or weapon in one of their hands?

Considering the class feature Tools Required and the guidance regarding components in the SAC:

What spells on the Artificer Spell List, TCoE, require the second class level or higher Artificer to have a free hand when they have access to an infused shield or weapon in one of their hands?

Considering the class feature Tools Required:

You must have a spellcasting focus—specifically thieves’ tools or some kind of artisan’s tool—in hand when you cast any spell with this Spellcasting feature (meaning the spell has an “M” component when you cast it).

and the complete guidance regarding components in the SAC, but mainly:

If a spell’s material components are consumed, can a spellcasting focus still be used in place of the consumed component? No. A spellcasting focus can be used in place of a material component only if that component has no cost noted in the spell’s description and if that component isn’t consumed.

What spells on the Artificer Spell List, TCoE, require the second class level or higher Artificer to have a free hand when they have access to an infused shield or weapon in one of their hands?