Umberto, I'm not sure you will find it better than a standalone version (I have both Stand. and ofx v5) in every situations...
It is true you can export from the ofx to a standalone project, export shapes etc and it is very cool, but honestly, if you consider an ofx version, you probably schedule to mostly remain inside Fusion, by adding a Mocha node which simply opens the Mocha interface .
Therefore you should first think about how are most of you projects requesting Mocha and the general workflow you choose. Maybe focusing on all the Mocha work first and then going to Fusion or else can be enough... Just to say that though it works good, the performance inside Fusion is way lower than in the standalone.
BTW, David wrote : "The plug in also works with Resolve".
While I didn't try again these days, it didn't a few months ago : I can see the OFX appear in the effects panel, I can even add it on a node but no mocha window would launch in Resolve. Tried within R 12.5, I will again now on v14 studio.
Edit : glad to see it's working now in Resolve, thx to this thread which made me try again 
*MacMini M1 16 Go - Sonoma - Ext nvme SSDs on TB3 - 14 To HD in 2 x 4 disks USB3 towers
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*Resolve Studio everywhere, Fusion Studio too
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