Repainting early 90s hardiplank cladding

[pedub]

My cladding is early 90s hardplank with very course texture and had not been well kept, its very dirty/red mould on it.
See photos

Is anyone able to offer advice how to prep this to repaint?
Dont want to waste my time and money painting if its not prepped right

The texture makes me think sanding it will be very difficult. Do I just clean/scrub it as best I can?

[risp]

Use a pressure cleaner/water blaster. 1500psi minimum or you'll be at it for ages (it'll take ages anyways). Hire one if necessary and try it without pre-treatment/spray product first.