Honestly you're better off updating/changing/removing whatever wrapper you're using that means you can't use SwiftPM directly. It's the future, is only going to get more ingrained as macros and build plugins mature so you'll need to do it eventually
Perhaps you could even extract this code into a SwiftPM command plugin and bring the feature "back" into SwiftPM that way. (To be clear, this is just an idea. I haven't investigated this and I don't know if it's possible. It may well be that the command plugin API doesn't provide plugins with enough information to replicate what the built-in command did.)