Power Supply for ESP8266 and PWM Fans

[c-bot-au]

I am building a small IOT/Smart fan controller for the cupboard that stores some of my network gear using an ESP8266 NODEMCU board, 2x 120mm 4pin PWM PC case fans and a DS18B20 temperature sensor. While I have a solid foundational understanding of circuits, power, power loss etc, this is a bit outside my knowledge so I needed to check if I'm right here.

My original plan was to use a standard wall plug 12v 1A Power Supply, route 12v direct to the fans, then step down to power the ESP2388 via 3.3v using either a MP1584EN or AMS1117 module (eg: https://www.aliexpress.com/item/32878789479.html)
Or this https://www.aliexpress.com/item/1005005691344779.html which uses 2 AMS1117 chips but has the built in multiple output and DC Jack for simplicity

However in thinking, rather than using another 240v wall outlet, can I just use one of the existing USB3.0 ports on the device already in there?
The fans are rated at 200mA each, the thermal sensor draws less than 1mA and from what I've read, the ESP82666 draws around 160-180mA (call it 200mA for arguments sake as it will be broadcasting data at regular intervals) in normal mode, and max of 300-400mA at startup only. That's a max current of maybe 800mA (and given the fans shouldn't start without the controller that's a very worse case scenario) and a running current of maybe 600mA.
USB3.0 seems to have a regulated output of 900mA, and up to 1.5A in battery charging mode.
Question 1 - My belief is that if powering the ESP8266 via the micro USB port, I can't (easily at least) pull 5v off one of the pins. Either way, pulling 3.3v or 5v off the board and trying to step it up to 12v doesn't seem like the best option.

Question 2 - If I use USB power input, run it directly to the VIN on the ESP8266, then also run it to a step up converter like a MT3608 (https://www.aliexpress.com/item/32644511449.html) or this https://www.aliexpress.com/item/1005005763935058.html, will that work?
If the USB only outputs 900mA, I know too much will be lost in the conversion, but would it pull 1.5A? And/Or would that damage the control board?

Powering it all off USB would be ideal, otherwise I go back to plan A.

[Railroader]

Could You please draw a schematic giving the picture?

[Deva_Rishi]

@c-bot-au

Powering it all off USB would be ideal, otherwise I go back to plan A.

Plan A sounds much better. Even just using a 7805 regulator in a TO-220 package together with 2 capacitors to step down to 5v and let the onboard regulator of the nodeMCU do the rest is easily sufficient. Stepping power up sounds like a plan as well, but the current draw from the fans may affect the power to the nodeMCU. Anyway, you know what i would do, but some other plans may also work just as well.

[c-bot-au]

Thanks. I think you're right, just bite the bullet and use the 12v that I know will work.
I ended up ordering both the dual AMS1117 unit and the MT3608 step-up with USB connector.
They're dirt cheap and ordered a pack of 5 each (I'll find other uses for them)

When I get a chance I'll draw a proper diagram then prototype them both out.
It sounds like my logic around the USB option is sound, so it's only going to be too low power and not circuit burning overload so I can try and test.

As for your other suggestion, I have some old MOFSETS, LM317S, 3805s and whatever around but I'd rather use a complete unit for simplicity given its been a while since I built that level of circuit and I have a tendency to mess things up.

[c-bot-au]

Ended up going with the 12v option and have successfully gotten it all working.
Rough image below of the circuit including the temperature sensor I added in and the resistor needed to pull up the voltage to read the tach signal.
The 2nd fan piggy-backs off the first with the included daisy-chain connector which works nicely.

I was having issues with the power and staying connected to the WiFi which is why I went with the 5v for VIN.