With the latest dev version I got the following two errors.

Audio.error.log:

Traceback (most recent call last):
File "/usr/bin/mycroft-audio", line 11, in
load_entry_point('mycroft-core==20.2.5', 'console_scripts', 'mycroft-audio')()
File "/usr/lib/python3.8/site-packages/mycroft/audio/main.py", line 69, in main
audio.shutdown()
File "/usr/lib/python3.8/site-packages/mycroft/audio/audioservice.py", line 466, in shutdown
self.bus.remove('mycroft.audio.service.play', self._play)
File "/usr/lib/python3.8/site-packages/mycroft/messagebus/client/client.py", line 213, in remove
self.emitter.remove_listener(event_name, func)
File "/usr/lib/python3.8/site-packages/pyee/_base.py", line 136, in remove_listener
self._events[event].pop(f)
KeyError: <bound method AudioService._play of <mycroft.audio.audioservice.AudioService object at 0x7fa7c8b970>>

skills.error.log

Traceback (most recent call last):
File "/usr/bin/mycroft-skills", line 11, in
load_entry_point('mycroft-core==20.2.5', 'console_scripts', 'mycroft-skills')()
File "/usr/lib/python3.8/site-packages/mycroft/skills/main.py", line 206, in main
skill_manager = _initialize_skill_manager(bus)
TypeError: _initialize_skill_manager() missing 1 required positional argument: 'watchdog'

The second is most likely because of my own requested service hooks ;)

If I understand it correctly, Python3.8 is a bit more picky on stuff. I know, Python3.8 is not yet officially supported, but as most recent distro already have it included I report them here.