Might need a BIOS update to do that. See THIS THREAD for exact same issue on another board. There's a discussion of a couple ways around it too. How many inputs are you allowing in your BIOS?

As an aside, your trolling comment about this forum is off-base, since many people here try to help when they have the time and the information in front of them. But you didn't bother to list any of your system specs or configuration, what and how you have things connected, no pics, and no history of your trial and error, so not sure what kind of magic answers were you expecting? You probably should indicate those things in this thread so people can help you better. 😉

I`m already on latest 1301 BIOS

I had before Maximus IX Formula and was not any problem to choose WATER IN or OUT sensor for fans profile source.

If they are grayed out then the only thing you can do is probe the BIOS for an option to turn them on. If that option doesn't exist you probably don't have it with this board, at least not yet under the current BIOS edition. In the thread I posted someone was posting water temp to sensor TS1, you might have to resort to that for now. There's also the other software if so choose, although I wouldn't prefer that solution myself. Do you have them connected to the correct headers, and do you have choice to select a different header?

If there's no option for it you might consider opening a separate thread with that request. Either under Software, or else maybe under Product Feedback.