I think there was mention about them being mobile, so they may come with a kit to make it easy to put them on locally manufactured vehicles. Taiwan has plenty of anti-ship missiles, but having more highly-mobile launchers would be a good thing for them.What is the point of operating land based Harpoon when land based HF-2 already exists? Seems needlessly redundant.
Plus the (regular) HF-II is a bit old. Block 2 has only just gone into production, although I don't know if that's going to be on a highly-mobile system given HF-III might be a better candidate.
Depending on what is actually part of the package, this could be Taiwan concerned that China could invade in the next 5 years irrespective of what they (Taiwan) do so they're looking to urgently acquire more high-quality anti-ship missiles.