Comment by amckenna

For not impressed I use one of these four:

- https://emojipedia.org/neutral-face/

- https://emojipedia.org/expressionless-face/

- https://emojipedia.org/unamused-face/

- https://emojipedia.org/face-with-one-eyebrow-raised/

For hypocritical smile I use this one:

- https://emojipedia.org/grimacing-face/

Obviously context shapes how these emojis are interpreted, but I find they hit the mark for those two expressions.