Agreed that you get more from Ranger 4 and 5 than fighter 4 and 5.
Hexblade is a warlock subclass, not rogue. Do you know what rogue archetype you want? I'm guessing given your mention of dueling style that you want to go rapier and shield, staying in light armor since you'll be maxing DEX? Arcane trickster might be a good fit, to give you a few more spells and spell slots (and a familiar, if you want one).
I encourage you to map out your progression level by level, not just the level 20 composition, and be clear with yourself about the tradeoffs involved each time you decide to level one class vs another. Even if the campaign does make it that far (which, even if everyone intends to stick it out now, is difficult to guarantee), nearly all of your play time will be at levels below 20.
I would probably start ranger and stick with it until 5, then maybe grab a fighter level now that you have two attacks to benefit from dueling style. From there you could either continue with fighter for action surge and maneuvers, or start taking some rogue levels for sneak attack damage and an ASI. If sticking with fighter it might be worth continuing to fighter 4 before switching to rogue (or take one rogue level then back to fighter 4) so you don't fall so far behind on ASIs. The end build (5/4/11) has exactly the same features as 5/3/12, except that the ASI comes earlier (I guess except that for an arcane trickster evel 12 advances your spell slots, but that seems minor compared to getting that second ASI several levels earlier).
You wind up with the normal complement of 5 ASIs in this build, which is good. You'll obviously want to use 1.5 or 2 of those for DEX bumps (depending on starting stats; if you do start with a 17 DEX, there's a case for starting with one level of fighter for CON saves, then taking Resilient (DEX) with your first ASI). You probably also want War Caster since I assume you'll have hands full, and will often be concentrating on something. Sentinel could be good, to round out the situations that prompt a reaction: Riposte if they attack you and miss, Uncanny Dodge if they attack you and hit, Sentinel if they attack someone else. Or you could take Defensive Duelist, to help you turn some would-be hits into misses. If you've got decent Wisdom, Magic Initiate (Druid) for Guidance and Faerie Fire could be nice. And there's always Lucky.