I had that new flame theory for a while now..coz..the hotter the flames get the more bluish theyy get... so sanji hasn't been soo pissed or infuriated to that extent in a while or at all to the point where he had to develop another technique .. plus it was Hinted in a movie too.. but makes sense if that happens.. prolly in midst of his fight with queen where queen makes fun of him or king.. and he turns blue lmao nah isn't gonna develop it in the dome.. against kaido IG but nah not in his first 1v1 in Post timeskip.. but then there is the problem of the base diable jambe getting dusted under the rug for the Pop Smokes blue devil version of it.. this has been a problem in DB universe for a very long timd where SSJ is shat upon due to SSGJ SSGBJ transformation being there so the initial transformation isn't valued enough soo.. its a bit cliche trope and too convenient for sanji coz alot of transformations would slide inconsistency in usage of other techniques when u already have a transcended version of the first one which makes it too convenient, unjust, and deplorable.. and inconsistent in a way that you could visually see ths orange flames to be intense but the latter half of your mind would say other wise.. coz intense now = BLUE DEVIL FLAMES that may cause issue too .. so i also get why oda chose not to go to that route now lol and rather than his flames changing color they turn into a miniature star or like far end of a jet exhaust where the flames coming out of the engine are rapid and intense.. which doesn't give it that vibe of a separate enhanced version of diable .. it just gives a vibe of diable jambe but intensified from its base state .. which is a very clever move by oda to avoid the flaw from occurring.. but in the movie they showed thay sanji's anger ignites blue flames from which the normal flames emerge soo he gave it that tint of blue to that it was intense.. which be be some in the anime again? idk
so no blue flames unfortunately Nope.. as much as it sounds as cool as SSJB.. nah too much of a compromise.