Welcome Frida and with a little searching, you will find much here about selecting machines. The first thing to know is that you will need a walking foot needle feed machine. Your first link above appears to be a cylinder arm walking foot machine but, I can't read the description.
A good test is to take some of the leather you will be sewing to the store and sew it. Be sure to sew corners and over multi layers just like you will be on your bags. You will probably sew with 92, 138, and/or 207 thread so you want to make sure all of those will work. By the links, you are probably not here in USA so machine numbers may differ some. There are many industrial machines that are not really suitable for leather, so try them yourself. You can look at the dealers here who have leather machines to get details. I don't think there is a dealer here selling Pfaffs but, the 1245 is a good flatbed machine for leather.
Best of luck in your search and glad to have you here.
Regis