The bioavailability of chrysin is so low that it is a completely useless supplement. If it did work as avertised, as an anti-estrogen, you would take it with your cycle like Nolvadex, to prevent gyno, not following your cycle to restart natural testosterone production like Clomid.
If you insist on using a natural supplement post cycle to resart test production, use tribulus. Get a good quality one like Tibestan or maybe Syntrax's ne Fuzu.