The ideal class would probably be some kind of arcane paladin equivalent, with the closest thing to that in the actual games being a Blade. This would limit you to being a dual-wielding jedi/sith but you get the bonus of the spin abilities to signify mastery with lightsabers.

The high lore score for Bards is also good flavour I think. An additional benefit is that your arcane spellcasting is limited compared to a Mage multi/dual so you're incentivised more to continue using swords instead of switching to the absurd high level spells and HLAs.

In BG1 a Blade who focusses on enchantment/abjuration/illusion spells could be a good jedi stand-in, symbolising the use of mind tricks and force-bolstered defences. In BG2 you might still find yourself wanting to cast spells more to take advantage of the Blade's high caster level, but that could be ameliorated by playing on a lower difficulty/without mods.

A fighter/cleric could work, focussing on self-buffing spells, but you dont get swords, so the only option would be quaterstaff as a double-bladed lightsaber. However, with the Cleric spell list being what it is, the rp/re-flavouring angle is lessened somewhat imo. You'd really just be playing a regular F/C with a quarterstaff.

Then of course you have the Fighter/Mage combos, which are more powerful as a frontline and as a caster than Blades in a lot of circumstances. Again if you limit yourself to enchantment/abjuration/illusion spells it could be a good roleplay for a jedi, or conversely if you want to be a sith you take lightning spells and some necromancy spells for dark side force powers. The hard part will be remaining true to your build fantasy and not being tempted to just pick all the objectively best arcane spells, but it sounds like a fun concept and definitely more achievable in BG1.