Wow, lots of ideas for places to trade Simmons. I thought I would compile and summarize. I am listing only the principal pieces, not every detail:
(More Added)
GSW: Wiggins/Wiseman for Simmons
WAS: Beal for Simmons/Maxey/Picks
Indy: Brogdon/Warren for Simmons
OKC: Draft Picks for Simmons
OKC/SAC: Fox for Simmons with Picks to SAC
POR: McCollum for Simmons
HOU: Gordon/Wood/Porter for Simmons
LAC: Leonard for Simmons
LAC: George for Simmons
DEN: Porter/Barton/Gordon for Simmons
DAL: Porzingis for Simmons
MIN: Russell/Beasley (or Edwards) for Simmons
SAC: Bagley/Hield/Picks for Simmons
SAC/BOS: Bagley to BOS, Pick to Philly
CHI: Lavine for Simmons
CLE: Sexton/Picks for Simmons
TOR: Siakam/VanFleet for Simmons/Maxey (or with Harris and Anunoby)
I think a SAC deal is probably the most likely of these. Philly wants Fox but SAC says no. SAC offers Hield, Bagley, and Picks (which isn't bad), Philly holds out. In the end, Hield, plus what they can get for Bagley and picks from a 3rd team is a good deal for Philly. I am not sure they will do better than that.
I think Beal is a wild card. So long as WAS believes he is happy, they won't trade him but if at any point they don't, getting Simmons, Maxey, and Picks would be a nice deal for them (and for Philly).