An update on the state of my system: last night I was having some new issues with Steam failing to recognize my Xbox controller. I could connect it using Bluetooth just fine, but it would not show up in Steam's controller configuration page and games did not respond to input. To be fair, I didn't really try to troubleshoot this very much, but I suspect it may be related considering it's libinput that's messing up here. I'll do some real troubleshooting this evening and put my results here.

infinitymdm You can exctract manually the files of libinput that you have donwloaded here:
https://packages.getsol.us/shannon/libi/libinput/libinput-1.18.1-36-1-x86_64.eopkg
Create a directory test and then extract the eopkg there with this command:
uneopkg libinput-1.18.1-36-1-x86_64.eopkg test. The extracted files are in test folder to avoid any mess in main folder. Then try to manually copy files.xml and metadata.xml to system folder where it belong.

After this try to rebuild database. sudo eopkg rdb

      zmaint I have tried sudo eopkg check. Unfortunately this fails with a similar error to those shown in the original post: missing files.xml / metadata.xml.

      I did take a look at the output of eopkg history, as this has helped me fix things in the past. However, the most recent entry was from the 24th, and things were working on the 25th and 26th.

        algent Using this method I was able to get things working again. Apparently libdbusmenu was also having the same problem, but I was able to fix by downloading the official package and reinstalling.

        I rebuilt the database, checked for errors, and was able to update my system once more. Thanks for your help!

            a month later

            Hello. This is the only place I've seen someone experience this issue as well, so I have to grab onto this thread. Today, I've installed Solus Plasma on my SSD while having Windows on a separate NVMe drive. I had trouble with trying to get Solus 4.3 to boot so had to resort to 4.1. After I got it fired up & installed without issues, I've rebooted the system for all the changes to take effect. To my surprise, the system does not boot anymore. It just gets stuck on a black screen with a blinking cursor in the upper left-hand corner, however I am able to change into another TTY session with the F-keys. Trying to update the system by doing sudo eopkg up. it gives me an error about missing file(s), especially metadata.xml. I am unable to do anything update-wise to the system as every similiar command to the one mentioned above results in the aforementioned error.

            What could be the reason for it? Missing GPU drivers? Something not playing well with my mobo? The metadata.xml was related to Kross if I remember correctly

              nolan Sadly, it didn't. Any commands related to packages give me the missing file error which doesn't let me proceed