The period ! one is the easiest to translate : you can say point final ! to close an argument in French. This is the same as it is in English, it refers to the punctuation mark, and can be used similarly.

Je t’ai demandé d’aller te coucher, point final !

Hands down actually translates to the opposite in French : haut la main. Facilement, or its more familiar form facile are equally used I guess. Another translation could be les doigts dans le nez, although it doesn’t fit in this context of superlative.

Il a réussi le test haut la main
C’est facilement le garçon le plus beau de la pièce !
Il les a facile tous battus
J’ai réussi les doigts dans le nez

Regarding bar none, the easiest translation is sans exception.

C’est le meilleur, sans exception

Now, if you want to say all three as an idiomatic expression in French, I don’t believe there is an super-hyperbolic expression consisting of 3 other hyperbolic expressions. I guess you will have to stick to only one of these… This is my best attempt at a literal translation :

C’est sans exception la meilleure chose jamais inventée, point final !

C’est de loin la plus grande invention de tous les temps, il n’y a pas photo !