Replaced inverter coolant pump and heat control valve, don’t know what to do!

An inverter overheats due to lack of coolant flow, or it could be a false indication due to a failed sensor.
A lack of coolant flow can be due to a pump failure, or clogged coolant passages, or it wasn't vented properly to remove air pockets when pump was replaced.

Do you have any phone apps that allow you to monitor the coolant temperature for the engine and inverter systems?

 

With the car in Ready take the cap off the inverter coolant reservoir and with a flashlight look inside the reservoir at the behavior of the coolant. Since it has fresh coolant it should look like the fluid is boiling
As it has very aggressive flow. That’s the way my coolant looks very very bubbling boiling look to it.
Good flow.

I assume you flushed the inverter loop and installed all new coolant using Toyota LLC coolant and bled it properly?
It’s the most important coolant loop.

Lastly you must have a Prius capable obd code reader it must have techstream software if not it may not
Pull all hybrid codes alerting you to a hybrid battery failure which will probably be next on your list of car woes.

The fact that you lost ac tells me it may be hybrid battery related anyway as that’s the first thing that happens when the hybrid battery fails it disconnects the high volt load to the ac system to preserve itself.

Get a proper code reading.