MAIN STRENGTHS: Very mobile, Hard to track, High flanking potential, Good against any hero, Can destruct the enemies easily
MAIN WEAKNESSES: Squishy, Can be nuked, Requires a lot of coordination with her movement and aim, Needs team to support her when starting to fight, Rarely can kill an enemy with one magazine
Favourable maps and modes: Tracer is best on Control (KoTH) maps, but can also be used on Escort and Capture. Maps like Illios, Lijang Towers, Kings row, Nepal are really strong for her.
Defend / Attack specifics: She is better when attacking, but in some cases can be used efficiently as defender too if played properly. Main focus should be to destruct and slow down the enemy team.
Synergises with: Zarya, Symmetra, Pharah
Countered by: Roadhog, Bastion, Torbjorn, A good Hanzo or Widow, Genji, Symmetra