Hi,
here is the meaning of the expression
"
as large as life (British, American & Australian) also as big as life (American)
if you say that someone was somewhere
as large as life, you mean that you were surprised to see them there
ex: I looked up from my paper and there he was, as large as life, Tim Taylor!
Cambridge Idioms Dictionary, 2nd ed. Copyright © Cambridge University Press 2006.
"
from
as large as life - Idioms - by the Free Dictionary, Thesaurus and Encyclopedia.
for a good translation in French, please can you provide some context for your sentence?