[RPG] Can you use the Shape Water spell to control the water generated by the Tidal Wave spell

The spell starts with this sentence:

Until the spell ends, you control any freestanding water inside an area you choose that is a cube up to 100 feet on a side.

All of the effects the spell list reference "the water in an area". Just as it says, the spell allows you to control the water in an area you choose. It won't create water, it will only control existing water.

Purely at the permission of your GM. It's physically reasonable, but clearly outside the wording of the spell. Some GMs will look at that an say, "that's a clever idea, sure." others will look at it and say "that's clearly more powerful than the spell is intended to be, no." 5e gives a lot of latitude to the GM in terms of rule interpretation. So if it's not clearly covered by the spell description, it's up to the GM's interpretation.

As a comparison, Arcane Lock is a second level spells that locks doors and/or windows (with some other benefits) so you're talking about using a cantrip in place of a 2nd level spell, which a DM may say is over powered.