Cyclone V part number 5CEBA7F27C8N

For Q2, Cyclone V device support hot-socketing feature where signals can be driving I/O pins before or during power up and power down without damaging the device. Refer https://www.intel.com/content/www/us/en/docs/programmable/683375/current/hot-socketing-feature.html. However, please be aware on the +-10% of 3.3V as it might exceed maximum value from the datasheet. Please also noted on the Power-On-Reset (POR) monitoring certain power supplies where it keeps the Cyclone® V device in the reset state until the power supply outputs are within the recommended operating range.

For Q3, both is correct as the I/O pins are tied to weak pull up that is why the pin is experiencing high impedance (High Z).