Reportedly, Huawei is preparing to announce a new foldable smartphone next month in China. Due to launch alongside the Watch D, the foldable will have a clamshell form factor like the Galaxy Z Flip3. Huawei's alternative should undercut Samsung's flagship on price, though.
https://www.notebookcheck.net/Huawei-tipped-to-release-a-cheap-clamshell-foldable-smartphone-next-month-mass-production-already-started.582082.0.html