The 23-year-old terminated his contract earlier this week following NAC's relegation from the Dutch Eredivisie.
The former Crystal Palace trainee has agreed an initial two-year deal, with the option of a further 12 months.
"Sullay is an exciting talent with bags of ability," Tangerines manager Terry McPhillips told the club website.
"He adds pace and power to our attack and hopefully plenty of goals and assists."
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