The files Coin.pc used by pkg-config and coin.cfg used by coin-config contain absolute paths which prevent an installation from being moved to another location, even though the latter includes a comment regarding a moveable package. This is also the case for simage, SoQt etc.

The CMake config files are already relocatable, as PACKAGE_PREFIX_DIR is calculated relative to these files via @PACKAGE_INIT@. Something similar could be achieved in Coin.pc by using setting prefix to ${pcfiledir}, see Helping C/C++ Packages be Relocatable. The other variables however would also need to be updated to be relative to prefix.

file(RELATIVE_PATH PACKAGE_RELATIVE_PATH "${CMAKE_INSTALL_FULL_LIBDIR}/pkgconfig" "${CMAKE_INSTALL_PREFIX}")
string(REGEX REPLACE "/$" "" PACKAGE_RELATIVE_PATH "${PACKAGE_RELATIVE_PATH}")
set(prefix "\${pcfiledir}/${PACKAGE_RELATIVE_PATH}")

coin-config already seems to calculate prefix based on its location, however the other variables are not defined relative to this.