Hi, Erin. Thanks for the welcome!
I'm not familiar with Swords & Wizardry. True20 is Green Ronin's
answer to WotC's D20 system, using only 20-sided dice. Versions of
True20 are used in Mutants & Masterminds and Blue Rose. It runs a lot
like 3e, with attributes (STR, DEX, etc.), skills, and feats. Powers
(spells/psionics) are treated like feats. There are no classes, but 3
"roles" (Adept, Warrior, Expert) that can be manipulated through
skills and feats to take the form of any class.
The skills are easy enough to convert, and I've already done that.
But it's a feat-heavy system and there are a LOT of feats. *If* they
convert, I'm guessing they're most appropriately converted to Perks or
Sperks.
And then there are the critters. There's a whole book of critters I
want to convert. Thankfully, Chimera is easy to wrap my head around.
Though it will be a lot of work, it shouldn't be difficult work.
~October
(The Elusive Female Gamer)