TheFork users who ate in Hoofddorp have said really good things about Tatsumi, Senbazuru and Red Orchids. Maybe you should give them a try!
Some of the more popular Sushi restaurants that offer vegetarian options on their menu in Hoofddorp according to TheFork users include:
Tatsumi, with a 9.4 rating
Red Orchids, with a 8.1 rating
Konomi, with a 9.2 rating