Mmm, I think they will.
The rule of thumb here is that in each game, Samus (and ergo Zero Suit Samus) is always based on the latest Sakamoto produced Metroid game that's out at the time.
As you can see, Samus is based on Super Metroid in Smash 64 and Melee, Zero Mission in Brawl, and (unfortunately) Other M in Smash 4.
Zero Suit Samus is a little more interesting. Obviously she's based on Zero Mission in Brawl and Other M in Smash 4, but her SSB4 design nonetheless appears to be an amalgamation of both, taking some details from the OM design while retaining the more aethletic form seen in ZM and Brawl. I'd imagine when the time comes for the next Smash, it'll be the same thing. Thankfully SR ZSS looks pretty athletic already as is.
That is, unless another Sakamoto Metroid comes along before then and completely changes her design again.