It works !

I've received the NodeMCU board first.

Plugging the rc522 module in the hardware SPI pins leads to crashing and breaking the IDEs console. Just connecting it, no running code. So until further investigation, no hardware SPI.

Using software SPI and pins D1, D2, D3 and D4, it worked right away, using the NodeMCU prefix.

For reference :

let spi = new SPI();
spi.setup({sck:NodeMCU.D2, miso:NodeMCU.D4, mosi:NodeMCU.D3});
var nfc = require("MFRC522").connect(spi, NodeMCU.D1);

I got everything else to work using software I2C too using D5 and D6.