I made an extra release of Okteta today (0.25.5) which adds the -DBUILD_OKTETAKASTENLIBS=OFF (default:ON) option, so only the core libs can be built when wanted, like here :)

There is also the kdevelop hexeditor plugin (plugins/okteta) which allows editing any files in kdevelop in raw mode as byte array (as in Okteta). But I am not sure who uses that, so have no idea if it is worth to add this to the appimage in general.
For that one would need to switch from -DBUILD_OKTETAKASTENLIBS=OFF to -DBUILD_DESKTOPPROGRAM=OFF -DBUILD_KPARTSPLUGIN=OFF. so that the additionally needed optional deps are build from the Okteta sources, and thus trigger the build of the KDevelop hexediting plugin by being present. For me enabling also this increases the size of the appimage from 111594888 to 112668040 (111410568 before this patch)