Xfdashboard is maybe a Gnome shell and macOS Expose like dashboard for Xfce.
Xfdashboard provides a GNOME shell dashboard and macOS Mission Control (e.g. Exposé and Spaces) like interface for use with the Xfce desktop. It can be configured to run with any keyboard shortcut and when executed provides an overview of applications currently open enabling the user to switch between different applications. The search feature works like Xfce's app finder which makes it convenient to search for and start applications.
See NEWS for details on changes and fixes made in the current release.
Xfdashboard archive or Xfdashboard tags
From source code repository:
% cd xfdashboard
% ./autogen.sh
% make
% make install
From release tarball:
% tar xf xfdashboard-<version>.tar.bz2
% cd xfdashboard-<version>
% ./configure
% make
% make install
Visit the reporting bugs page to view currently open bug reports and instructions on reporting new bugs or submitting bugfixes.