Using NEHotspotConfigurationManager.joinAccessoryHotspot(_ accessory: ASAccessory, passphrase: String) to connect the WiFi, but this function implicitly sets joinOnce to YES.
Is there any api that can use ASAccessory to connect to WiFi while maintaining JoinOnce = false. Is it possible to open up this feature？
At this point it is not possible do this. If you would like Apple to consider such a feature, we would invite you to file an Enhancement Request using the Feedback Assistant.
A successful Enhancement Request will explain how this will benefit your users. If you have any questions about filing a enhancement requests and bug reports, take a look at Bug Reporting: How and Why?