Last new topic for today at least (new owner).
Can I use any wall charger up to and including fast chargers (that I normally use with my phone) with the Q35 headphones, without risk of causing damage quickly or over multiple uses?
Yes you can use any USB charger without risk of damage.
Worst case it doesn’t work.
There are different charging protocols like PD, QC3, Dash, etc but they only give higher voltage if the other end negotiate a common protocol.
Q35 isn’t any of those protocols, so the most common is 5V 1A is presented, or doesn’t work at all.
Just plug in and find out.
The only way anything can damage if it’s a jerrywrigged non USB charger which just presents a high voltage without negotiation. You’d have made up one with a soldering iron… Your phone charger isn’t that.
Yes you can
yes you can. See the @The_Professor 's answer. As always he does a good job explaining how it works.