Best counter-picks
These heroes are listed as strong answers into Ana.
Tank
WinstonAna has great difficulty dealing with Winston's dives. Sleep is her main counterplay
ZaryaEven if hit by Biotic Grenade, Zarya can cleanse it with her barrier
D.VaHer attacks are easily absorbed by D.Va's Defense Matrix. Ana has great difficulty dealing with Booster engagements
D.MonAna has little mobility; if D.Mon closes in, Barrier can contest Sleep Dart and Biotic Grenade while D.Mon pressures her.
Damage
GenjiAna has difficulty dealing with Genji's close-range pressure. Her attacks can be reflected by Deflect
TracerAna has difficulty dealing with Tracer when she engages at close range
FrejaAna lacks mobility, making her vulnerable to Freja's poke. Freja can stay at range where Ana's abilities are hard to land
Support
LúcioLucio can use speed boost to help teammates close in on Ana
KirikoKiriko can cleanse Biotic Grenade anti-heal with Protection Suzu
WuyangWuyang can poke Ana at mid-range where she's vulnerable
Favorable targets
Ana is listed as performing well into these heroes.
Tank
RoadhogAna's Biotic Grenade can prevent Roadhog's Take a Breather healing. Sleep Dart can interrupt Roadhog during his hook combo
MaugaMauga is very easy to hit with Ana's Sleep and Biotic Grenade
HazardHazard has no barrier, making him vulnerable to Ana's Sleep and Biotic Grenade
Damage
BastionBastion's large hitbox and very slow movement in Configuration: Assault form make him vulnerable to Ana's Sleep and Biotic Grenade
Support
MercyAna's Biotic Grenade can disable Mercy's healing. However, Mercy's mobility makes her hard to hit