It's a non-steroidal anti-androgen similar to darolutamide, enzalutamide, or bicalutamide. It binds directly to T and DHT receptors. It definitely WILL work, the question is "how strong are the side effects" and "what is the lowest effective dosage".
I can't find any info about the binding affinity (higher is better for topicals so that more of it binds before going systemic). The serum half life is low at 6hr which is good so there will be less systemic buildup.
There two common side effects of this type of drug
-gyno. This is mostly an issue with bicalutamide because it has a long half life (7 days) and relatively low bidding affinity.
-anxiety. This is an issue with enzalutamide, and to a smaller degree darolutamide, due to off-target GABA receptor inhibition in the brain. I think some people are more sensitive to this than others. Darolutamide has less blood-brain barrier penetration so the side effect is less severe than enzalutamide.
Studies of fluridil usually use a 2% solution and they were effective. It can probably go lower. There are some older threads on the forum about fluridil but honestly not much information. I recommend you check the threads about topical enzalutamide, darolutamide, and bicalutamide to get an idea of side effects.