[giomasce]

First: you don't necessarily need an alternative chroot, Debian allows installing packages of foreign architectures in the same main tree. It has some hiccups, but it should mostly work.

Second: of you like playing with foreign architectures, I have a collection of ready to boot Debian images of many architectures, that you can promptly boot with QEMU. Command line included. It is mostly aimed at full system emulation, though (but if you look through the cogs you can also download chroots). https://people.debian.org/~gio/dqib/