Meshbake

Video 1: Demonstration
Video

Video 2: Reducing drawcalls from 7700 to
1000 with MeshBake

Video 3: Merging modular Skeletal Meshes
to one output Skeletal Mesh while also baking the
materials

Documentation

Discord

Forum Thread

New Features in 1.7:

• Morph Target baking. Active Morph Targets on selected
  actors can be baked directly into the baked mesh geometry. A button
  has been added to the SkeletalMesh editor viewport that will select
  the preview mesh in the SkeletalMesh/Animation editor viewport when
  clicked. This allows for any Morph Target values set in the editor
  window to be quickly baked out to a new model directly from the
  SkeletalMesh editor window.
• Merging of identical UV mesh sections into a single shared
  UV space. Identical source mesh sections will share a single
  unique set of UV values in the baked output mesh.
• Low memory mode. Enabling Low memory mode greatly
  reduces the maximum memory usage while baking, at the expense of
  being slightly slower in certain cases. If your system is paging to
  disk while baking, enable this option to help prevent paging and
  greatly reduce the total baking time.

New Features in 1.2: Skeletal Mesh and Static
Mesh merging. Modular Skeletal Meshes can now be merged together in
the editor quickly and easily.

MeshBake is a C++ plugin that allows in-editor baking and
merging of materials and sections for both Skeletal and Static
meshes. MeshBake allows you to bake meshes without leaving the
editor, thus avoiding the cumbersome importing and exporting of
assets and recreating of materials that would normally be required
when baking with a third-party program.