Beasley was ejected in the third quarter after getting into a minor scuffle with Draymond Green.
Per The Athletic's Anthony Slater, Beasley and Green appeared to smooth things over immediately after the incident, but officials thought Beasley was trying to "re-engage" the Warriors forward and gave him a technical.
"Looking back on it, it looked, I looked pretty aggressive, especially I guess with my MO," Beasley told reporters. "Draymond is one of my really good friends."
The officials threw Stephenson out in the fourth quarter for appearing to throw a punch at Quinn Cook after being fouled.
Despite finishing the game shorthanded, the Lakers secured a 119-105 win over the two-time defending NBA champions by erasing a 17-point deficit. Friday's game was the final preseason tune-up for both teams.