@knobby22 I believe most of the best 90kg lifters are around 98-100kg, and certainly it's possible to be that heavy and cut without problems (so why not?).
Yes, I'd aim for 4-5bs through water manipulation and glycogen depletion (no carbs for a couple of days before), then cut around 8-10lbs via sweating and go to bed around 200-202lbs. The last bit can be lost overnight and with gum / spitting or more sauna time just before the weigh in.
I'll add that I'm certainly no expert though, as I've never cut more than about 5kg. People like Chris Duffin, Kevin Oak, Matt Kroc (previously), Amit Sapir, Dustin Reed on this site, etc. have all cut significant amounts of weight and have their own protocols. It might not be easy, but rest assured it's possible to cut huge amounts of weight if necessary; the problem becomes recovery afterwards with more extreme cuts.