I have tried that with the following result:
# wget -O -
http://ppcutopia.ddns.net/repos/apt/conf/public.gpg.key|apt-key add -
--2020-01-02 09:25:27--
http://ppcutopia.ddns.net/repos/apt/conf/public.gpg.key
Resolving ppcutopia.ddns.net (ppcutopia.ddns.net)... 104.159.217.5
Connecting to ppcutopia.ddns.net (ppcutopia.ddns.net)|104.159.217.5|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 2864 (2.8K) [application/pgp-keys]
Saving to: 'STDOUT'
- 100%[===================>] 2.80K --.-KB/s in 0.002s
2020-01-02 09:25:27 (1.55 MB/s) - written to stdout [2864/2864]
OK
# apt update
Get:1
http://ppcutopia.ddns.net/repos/apt/debian sid InRelease [2,216 B]
Get:2
http://ppcutopia.ddns.net/repos/apt/debian fienix InRelease [2,200 B]
Get:3
http://ppcutopia.ddns.net/repos/apt/debian sid/main powerpc Packages [1,975 kB]
Get:4
http://ppcutopia.ddns.net/repos/apt/debian fienix/main powerpc Packages [72.6 kB]
Fetched 2,052 kB in 11s (195 kB/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
7 packages can be upgraded. Run 'apt list --upgradable' to see them.
# apt install abiword
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
abiword : Depends: abiword-common (>= 3.0.2-9) but it is not going to be installed
Depends: libabiword-3.0 (>= 3.0.2) but 3.0.0-8+b1 is to be installed
Depends: libloudmouth1-0 (>= 1.3.3) but it is not going to be installed
Depends: libots0 (>= 0.5.0) but it is not going to be installed
Depends: librdf0 (>= 1.0.17) but it is not going to be installed
Depends: librevenge-0.0-0 but it is not going to be installed
Depends: libtelepathy-glib0 (>= 0.13.0) but it is not going to be installed
Depends: libtidy5deb1 (>= 1:5.2.0) but it is not going to be installed
Depends: libwmf0.2-7 (>= 0.2.8.4) but it is not going to be installed
Depends: libwpd-0.10-10 but it is not going to be installed
Depends: libwpg-0.3-3 but it is not going to be installed
Recommends: abiword-plugin-grammar but it is not going to be installed
libabiword-3.0 : Depends: libcamel-1.2-49 but it is not installable
Depends: libchamplain-0.12-0 (>= 0.11.0) but it is not going to be installed
Depends: libchamplain-gtk-0.12-0 (>= 0.11.0) but it is not going to be installed
Depends: libclutter-1.0-0 (>= 1.10.0) but it is not going to be installed
Depends: libclutter-gtk-1.0-0 (>= 0.91.8) but it is not going to be installed
Depends: libcogl-pango20 (>= 1.17.4) but it is not going to be installed
Depends: libcogl-path20 (>= 1.17.4) but it is not going to be installed
Depends: libcogl20 (>= 1.17.4) but it is not going to be installed
Depends: libebackend-1.2-7 but it is not installable
Depends: libebook-1.2-14 (>= 3.5.91) but it is not installable
Depends: libebook-contacts-1.2-0 (>= 3.7.90) but it is not installable
Depends: libecal-1.2-16 (>= 3.5.91) but it is not installable
Depends: libedata-book-1.2-20 but it is not installable
Depends: libedataserver-1.2-18 (>= 3.5.91) but it is not installable
Depends: libegl1-mesa (>= 7.8.1) but it is not going to be installed or
libegl1-x11 but it is not installable
Depends: libical1a (>= 1.0) but it is not installable
Depends: libpng12-0 (>= 1.2.13-4) but it is not going to be installed
Depends: libraptor2-0 (>= 2.0.14) but it is not going to be installed
Depends: librasqal3 (>= 0.9.31) but it is not going to be installed
Depends: librdf0 (>= 1.0.17) but it is not going to be installed
Depends: libwmf0.2-7 (>= 0.2.8.4) but it is not going to be installed
Depends: libwv-1.2-4 (>= 1.2.9) but it is not going to be installed
libreadline6 : Depends: libtinfo5 but it is not going to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).