i don't understand your question.
importable module from Terminal without using SPM: this means import a module in REPL?
I'm still unable to import the generated module in a swift program: this means that you want to import a module (without sharing sources) in another swift project? Or simply import the module.
Import shared object
Compile your client module with
swift build -Xswiftc=-I -Xswiftc LIBPATH -Xswiftc -L -Xswiftc LIBPATH -Xswiftc -lLIBNAME
where LIBPATH is the folder which contains .swiftmodule and .so library file and LIBNAME is the standard unix library name.
Library project should use this piece of Package.swift file
.library(name: "LIBNAME", type: .dynamic, targets: ["LIBNAME"])
to produce a shared library file .so.
Import simple module
To import a module you should import a repository with the
.package(url: "GITURL", from:"TAG")
Import module in REPL