If you want i can do a list for you of everything that counters him 
:
Mc Cree flashbang
Hanzo broken headshot
Roadhog hook
Roadhog ult during Death Blossom
Sigma Rock
Sigma ult during Death Blossom
Sigma black hole
Rein hammer down
Rein charge
Every type of shield during Death Blossom
Ult of Zen and Lucio
Sombra hack and emp
Ana sleepdart and biotic grenade
Any hitscan during death blossom can easily kill him
Junkrat grenade that makes you a flying ballerina
MEI
Brigitte shield can easily stop Death Blossom
Phara boop
Lucio boop
Symmetra Ult
Doomfist punch
Genji deflection
Diva barrier
There’s more but now you know and as i say before more than half of them counter him 
