Let me follow other people's lead and assume that "barefoot"
still includes boots and blades
Skating without an insole at all would expose your feet to the nails, staples and such- and that seems like it would hurt.
Some skates expose those things if you remove the insole, some don't.
My skates don't have any big bumps beneath the insole, but my feet have have a mild allergic (or other sensitive) reaction to skating without anything - perhaps a chemical sensitivity to the preservatives in the leather - so I don't skate barefoot.
You could replace the insole with a sheet of leather, paper or cardboard, or anything else, cut to the same shape, to provide similar protection. Or you can glue in your current insole, so it can't slip, which is one reason some people prefer barefoot. Use glue that doesn't stick too hard, so you can play with or replace the insole later.
If you glued Velcro or generic equivalent to your socks and boots, you could turn your socks into liners that wouldn't slip either, so would feel somewhat like skating barefoot, but with padding. (But put in the wrong place, the Velcro would create an undesirable bump.) But don't glue your socks in - without preservatives, they would soon rot, stink etc.