K-Line ECUs writing is not supported by HTS CANBus right now. There is no plan for when they might be supported yet. But who knows, things could change in the future
What you can do for now is that you can load K-Line ROMs into HTS CANBus. Some K-Line ROMs are defined, and you can use HTS CANBus to import/edit/tune the already supported ROMs.
K-Line ROMs cannot be read over OBD2 port.
For ECU Write. Settle with PCMflash or MMCFlash(also called MMC Flasher). They require official Tactrix Openport 2.0 to work with. And you will have to purchase the dongle key for PCMflash or MMCFlash to work. And then buy the Honda K-Line module to activate Honda K-Line ECUs writing feature
Said software will have original Honda K-Line ROMs for the activated users. So, if your K-Line ROM is supported by HTS CANBus. You just have to select the ROM from the lists that is a match to your ECU. And then import the ROM to HTS CANBus to do the editing/tuning.
This is a screenshot of working MMCFlash writing ROM to a Honda CANBus ECU.
K-Line ones are greyed out because it's not activated in this account/dongle.