Use .p.wrap https://code.kx.com/q/ml/embedpy/userguide/#embedpy-objects_1
Example giving each subplot a title:
plt:.p.import[`matplotlib;`:pyplot]
plts:plt[`:subplots;<;pykwargs `ncols`figsize`dpi!(2;24 8;100)]
.p.wrap[plts[1;0]][`:set_title]"Plot1";
.p.wrap[plts[1;1]][`:set_title]"Plot2";
plt[`:show][];
Result: