  We revisit $T\bar T$ deformations of $d=2$ theories with fermions with a view
toward the quantization. As a simplest illustration, we compute the deformed
Dirac bracket for a Majorana doublet and confirm the known eigenvalue flows
perturbatively. We mostly consider those $T\bar T$ theories that can be
reconstructed from string-like theories upon integrating out the worldsheet
metric. After a quick overview of how this works when we add NSR-like or
GS-like fermions, we obtain a known non-supersymmetric $T\bar T$ deformation of
a $\mathcal{N}=(1,1)$ theory from the latter, based on the Noether
energy-momentum. This worldsheet reconstruction implies that the latter is
actually a supersymmetric subsector of a $d=3$ GS-like model, implying hidden
supercharges which we do construct explicitly. This brings us to ask about
different $T\bar T$ deformations, such as manifestly supersymmetric $T\bar T$
and also more generally via the symmetric energy-momentum. We show that, for
theories with fermions, generic such choices lead us to doubling of degrees of
freedom, with potential unitarity issues. We show that the extra sector
develops a divergent gap in the "small deformation" limit and decouples in the
infrared, although it remains uncertain in what sense these can be considered
as a deformation.
