Hi Guys!
We ran into the same problem: PN532 V3 Module from elechouse and try to use it with I2C. After nfc.begin it stuck and no answer from module.
After a lot of digging we found a solution. If you are using the Library which is extended with HSU compatibility in the end of PN532/PN532.h file there is the declaration of the buffer:
uint8_t pn532_packetbuffer[255];
If we changed the pn532_packetbuffer array size from 255 to 64 then the I2C communication starts immediately and the module could read data from tags. So the line in the header should look like this:
uint8_t pn532_packetbuffer[64];
Probably the buffer size was changed because of the HSU communication, while in the original repository this value is still 64, but unfortunately it does not fit to I2C communication
Hope this helps for some people, who have the same problem.