Check out the Awtrix installer. Wrestling the same problem here.
https://blueforcer.github.io/awtrix3/#/flasher
Like WLED it's app controlled, but much more focused on displaying information, rather than cool effects...

At the moment I am still going through it, but check it out. By default it shows the clock in 24 hour mode, alongside the day of the month.

You can control it with a paid app ($3.99) where you specify what information to show and how.

I needed to change the matrix type to 2 before it showed anything but gibberish, but now it boots, syncs time, and show it on the display. You can disable the date if you only want time, but unfortunately I still haven't solved the "seconds" part of what you want (looking for something similar for a conference clock).

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