I had the Apple Store replace the battery on my iPhone SE 2nd Ed (2020) on 9/13/26 and I updated the operating system to iOS 27 a couple days later. I immediately encountered the same charging issue described here. It charges perfectly normally with any USB-A to Lightning charger, including higher-voltage USB-A fast-charging ports on my computer. But if I plug it into any USB-C to Lightning charger, it charges for exactly three seconds and then drops the connection.
Thinking the issue was a botched battery replacement, I brought it back to the Apple Store for a warranty claim on the battery service. They put in another new battery and ran full diagnostic testing and did a full software reinstall. They found no visual evidence of damage or shorting. They said it is able to accept fast charging through Mag Safe and can charge fine from USB-A, but they confirmed it will not charge from USB-C. They were unable to isolate the cause. The only explanation they could think of was short on the logic board, but they claimed there was no way this could have happened during the battery replacement.
Sounds like I falsely accused them and it was the iOS 27 update all along!