Zafina is a stance character, which means she has several different stances that she can be in for a long time, and they play a huge role in her gameplan. In Tekken 7 she has Scarecrow, Mantis, and Tarantula.
Scarecrow (SCR) is entered by pressing 3+4, can also manually leave it by holding d/b. Zafina also has several moves that automatically enter SCR, and the transition can be cancelled by holding back. Scarecrow cannot block, doesn't evade by itself, and doesn't have parries, but it has frame 6 powercrush i14 SCR 4, frame 10(?) low crush i18 SCR 3+4, and frame 6 high crush i19 SCR d/f+4, in SCR she also has the most damaging launcher, i17 SCR 1+2, which does very good advantage on block. (There is also frame 1 high crush with manual MNT, SCR d+3+4)
With all that, Scarecrow is a pressure based stance, moves that enter SCR give very good advantage (+7/-2 on 10f punisher), stance itself provides both good reversal options, and pressure options. It creates an interesting game, as on block opponent can generally challenge SCR to avoid continued pressure, yet the reversal potential is still present, but those reversals are themselves very punishable.
There also is SCR 3,f+3 loop, if second hit gets blocked, another SCR 3 has to be blocked. SCR 3,f+3 second hit is duckable, and thus punishable, but it's not the only move there, SCR 3,3,4d when second hit is CH, third hit is guaranteed, and it's a launcher. On block it's only -14, though it is low parriable. But also you can decide to not finish the string, it is launch punishable on hit, but there are a lot of mental frames
Mantis (MNT) is entered by using d+3+4. The moves that can transition to MNT typically require you to hold down to transition. The stance can block mid by holding back, it can block low by holding d/b, but it results in the commitment, as it also triggers a long leaving stance animation. It doesn't crush highs, but it evades a lot of highs and mids. Evading also depends on the animation phase. The only moves that give good Mantis are d+3, and SCR d/f+4. d+3 is +4 on hit, allowing MNT 2 and MNT 1,3 be frame traps, no low attacks are frame traps, but opponent has to use a cruch jab to interrupt, and it simply isn't worth the risk of getting CH launched by MNT 2. To avoid the mix up opponent should quick sidewalk left into low parry, which is hard, and doesn't work on P2, that's why d+3 is such a good move. SCR d/f+4 is +7, so the mix up is always true. Otherwise transitions to mantis are about -13 on block, which is very good, but it neans opponent can now always sidewalk the stance either side and punish whiffs potentially for much more than they could punish -13 (MNT d/f+2 tracks left, MNT 4 tracks right, and MNT d/f+4 is homing)
Tarantula (TRT) is entered by using d+1+2, can leave it by holding d/b which triggers a very long animation. The moves that can transition to TRT typically require you to hold down to transition. Tarantula cannot block, it doesn't crush highs nor lows, it's technically a white airborne, but it does evade most highs, a lot of mids, and probably even some lows. Sometimes it's punishable on hit, and when it's not, it's a reasonably rewarding repeatable mix up between TRT 3 and TRT 1, TRT 1 resets the mix up, and TRT 3 gives a decent damage and knockdown. But whenever there isn't a mix up opponent can walk either direction to the back, and if they have life lead, just wait until Zafina quits the stance. Zafina can do nothing about it. She can try to run away, and if opponent doesn't have life lead, and really just needs anything, running stomp will always work. Other TRT moves are practically useless at high level for being way too slow, and way too linear. Although TRT 1+2 is a decent js7 low crush, but at high level there isn't much place for it.
Also opponents may struggle punishing TRT, as its evading properties with the airborne state don't allow a simple d/f+2, so the punisher depends on character. Lei, for example has f,f+2, which is a genuine punisher for 1,4 on hit due to it being a power crush, and it launches. Zafina herself on the other hand can't truly punish 1,4 on hit, but she can attempt d/f+1,4 or f+2,3 which will both hit Tarantula and convert to combos.