Found a method of getting over the guard gates by using eris (See video example) (Tested on 3DS)

TLDR You can keep resetting Eris's homing attack animation by standing next to specific walls.

AFIK You can skip Eagle library and maybe rhino caves *Rhino caves Untested.

Can't get into swamp early yet because of the rhino barrier and the rhino hub you can't clip into using this method.

Besides the current findings im out of ideas on how to push this.

If anyone finds anything else just DM me.