The PDAL PCD Writer can write .pcd files. For it to work, you must have linked the PCL libraries at compile time. The PDAL OSGeo4W build does not have PCL support. If you are unable to build PDAL with PCL support yourself, one possibility is to use PDAL's Docker containers to achieve your task -- those have PCL linked.
Then, simply run pdal translate:
As commented here, if you get error:
PDAL: Couldn't create writer stage of type writers.pcd
Basically it says, there is no PCL plugin. Hence, you should show library or rebuild PDAL with PCL plugin option to check for build.
There must exist writers.pcd Write data in the Point Cloud Library (PCL) format.
If the plugin ...
With PDAL it would be the opposite from Converting .las to .pcd file using PDAL?:
pdal translate input.pcd output.las
In this case, you will need to enable the PCL libraries, so the PDAL PCD Reader can work.
PDAL is a little tricky to get started. Its developers advise beginning using it with PDAL's Docker.