First, since I neglected to say this earlier, thanks for your willingness to help

That sounds like a reasonable expectation.  The more things that "just work," the better, IMO.  Obviously, advanced users can remove / customize things however they want.  So for this particular example, there would need to be some way for the installer to detect that it's being run inside a vm.  Some questions: would it make sense to install qemu-guest-agent inside a gui-less guest (no desktop)?  What about spice-vdagent?  Personally I prefer virtualbox -- I tried the switch to qemu for about 3 weeks and then switched back.  Unfortunately the two do not like to play together either -- when running vb I can't use kvm with qemu.  Anyway, that's a bit beside the point, other than to say I don't have a lot of qemu experience.

I believe it would be viable IF someone were to fork kde 6.7.6 and maintain it for devuan.  That someone is not me.

This one seems like "too soon to adopt."  From https://github.com/orgs/Sonic-DE/discussions/28 "we don't currently have packagers for the Debian family of distros"

It may be that the "img" file is of the device, but you're trying to write it to a partition.
What does this show fdisk -l /media/storage/isos/chimaera/rpi_chimaera.img

This sounds like a reasonable explanation.  The better fix, then, as you mentioned, is to re-create the hwdb.  run this as root:

udevadm hwdb --update
service eudev restart

This works with my hp g3010 scanner, no need for custom udev rules.

Which version of devuan - daedalus (oldstable), excalibur (stable), freia (testing)?

Thanks for the report.  Fixed in September 19 netinstall iso.

This isn't "how to avoid the problem" - but if you have difficulty with their picture captchas, this may be of help.
After spending about a half hour clicking on buses, traffic lights, crosswalks, bicycles, stairs, fire hydrants, cars, bridges (and probably more!), in a never-ending cycle, eventually I tried the audio captcha instead.  This took only about 5 tries to get it right, and then I could proceed.  All the sound samples had static, most were entirely unintelligible to me.  Just load a new one until you get one that you can understand.

I've got this script (for an example) from when I used to hibernate/suspend.  It might require pmtools pm-utils (as Ralph noted above).

#!/bin/bash
# Script name: /etc/pm/sleep.d/50_network
# Purpose: Restore network settings upon thaw / resume

case $1 in
  suspend|suspend_hybrid|hibernate)
    :
    ;;
  resume|thaw)
    # wait 10s for network to come back
    sleep 10
    logger -s "/etc/pm/sleep.d/50_network: Restoring network settings..."
    # restore network settings
    /usr/local/sbin/netconfig.sh
    logger -s "/etc/pm/sleep.d/50_network: Done."
    ;;
esac

Yes, there's firmware-mediatek_20260810-1_all.deb

However, I found in firmware/Contents-firmware:

/usr/lib/firmware/mediatek/mt7925/BT_RAM_CODE_MT7925_1_1_hdr.bin firmware-mediatek_20260622-1_all.deb non-free-firmware
/usr/lib/firmware/mediatek/mt7925/WIFI_MT7925_PATCH_MCU_1_1_hdr.bin firmware-mediatek_20260622-1_all.deb non-free-firmware
/usr/lib/firmware/mediatek/mt7925/WIFI_RAM_CODE_MT7925_1_1.bin firmware-mediatek_20260622-1_all.deb non-free-firmware

So it appears I need to update the Contents-firmware file to the correct version on the disc image.
Hopefully it will all be good in the next iso (check mirrors in a while)

Thanks for reporting this.  I'll update the freia installer soon...  it still was using the excalibur Contents-firmware file which I believe is the source of your issue.

Another option...

With qemu, use -nic user option, and set up networking as follows

ip address add 10.0.2.15/24 dev eth0
ip link set dev eth0 up
ip route add 10.0.2.0/24 dev eth0
ip route add default via 10.0.2.2 dev eth0

Also, your /etc/resolv.conf should contain

nameserver 10.0.2.3

From there, you should be able to apt install dhcpcd-base or whatever package(s) you want.

With virtualbox, you could change the network to bridged, and set up static networking as though it were a physical device on your LAN.  For example, if your LAN uses 192.168.1.0/24 with a gateway of 192.168.1.1 (I think this is a common default setup), you could do something like this

ip address add 192.168.1.20/24 dev eth0
ip link set dev eth0 up
ip route add 192.168.1.0/24 dev eth0
ip route add default via 192.168.1.1 dev eth0

Obviously, you'd want to use an address not in use by another device.  That was just an example.

from what I'm seeing on daedalus, nvidia-driver and nvidia-kernel-dkms are at version 535.261.03-1 (daedalus), 535.309.01-0+deb12u1 (daedalus-security), and oddly 535.216.03-2-bpo12+1 (daedalus-backports).
maybe this would work?

apt install nvidia-driver/daedalus-security nvidia-kernel-dkms/daedalus-security

Of course, you'll need to have apt working properly first.