Hello,
1 - You can generate serials in the backend and export them (in CSV/XLS format). If you can create hardcopy thanks to EAN13 codes, it should suits to your needs.
It is also possible to import serials in the backend, so if you have a list of your EAN13 codes, you can import the part that you want to sold online.
2 & 3 - A barcode scanner is just a tool which can read a barcode. It must be connected to something to perform "actions".
If you want to be able to tell if a ticket is valid or not, you need something with "connectivity" so it can check that.
The usage of a phone with a QRCode offer the simplicity of having an URL which will be open in the phone and tell the result.
But if you already have all that is required with a barcode scanner, you can open a special page in the website and perform the "serial consumption" which will gives the status of the ticket.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.