But this is only on the switch, and not sure if this would have impact unless you have some extreme load on your network or a very slow connection and all devices creating the load is behind this switch… Or that they might have some logic her in software for compensating for some quite poor processing power for the switch?

Could be that is something put there as it “looks good in marketing”. Instead buy a better switch…

The ports have different traffic priority. Green = High, Yellow = Medium, Grey = No priority.

In addition to the router having an USB-port, it need to have support for sharing the USB-storage device in software.

My ISP gives out two public IPv4-addresses. It is not that common for ISPs to provide multiple IPv4-addresses today.

On the other questions here, No.

(Remember that IPv6 is a different story…)