Add the following Framework Search Path in the Build Settings of your target:
$(SYMROOT)/Release$(EFFECTIVE_PLATFORM_NAME)
and make it non-recursive
In my case this was for Alamofire, which was added to my project as a git submodule.
The framework was being built correctly which can be seen in the build logs, but I assume the default framework search path is derived from the scheme name. The Alamofire framework & dSYM file are in Release-iphoneos/ Release-iphonesimulator.
This should work work with any Swift framework as long as it’s scheme names are default. If not, check the build logs and adjust the framework search path accordingly.