Sam Asghari Seemingly Shades 'Professional Father' Kevin Federline

We are sensing some K-Fed shade from Sam Asghari ... who hinted at his feelings about Britney Spears' ex-husband releasing a tell-all book when we caught up with him in Los Angeles Friday.

Check out the clip -- the grinning actor says Kevin is a "professional father" ... adding it'll be "great" for him to share the first-ever book instructing dudes how to be one.

ICYMI ... Kevin announced his upcoming memoir, "You Thought You Knew," earlier this month. It promises to detail the highs and lows of his time in the spotlight along with fatherhood and marriage to the Princess of Pop. He also calls himself "one of pop culture’s most misunderstood figure."

Kevin shares 2 kids with Brit -- Sean Preston and Jayden James. He largely raised them after she lost custody in 2007, but Britney has seemingly put effort into patching their relationship in recent years.

The former dancer is also dad to daughter Kori and son Kaleb with his ex Shar Jackson, and shares daughters Jordan and Peyton with his wife Victoria Prince. The pair have been married since 2013.

Back to Sam -- he also tells us he and his girlfriend, realtor Brooke Irvine, are doing "amazing."