5. AJ Green
Another veteran, Green has been mentioned as an option for the Chargers in 2021 and 2020. Like Watkins, Green will be cheaper than a young receiver, as Spotrac has him listed at 4 years $7 million avg/year. Four years is a lot for a 33-year-old, and I don't think he gets offered more than 2 years anywhere.
After 10 seasons in Cincinnati and one in Arizona, Green hits the free-agent market as an experienced veteran and might be looking to sign with a contending team and make a push for a ring before he ends his career.
Tom Telesco has preferred tall receivers in the past, and Green is 6 foot 4. Green has been known throughout his career because of his consistency and big-play ability, and that hasn't been lost yet. This past year in Arizona he posted a 15.7 yards per reception mark, which is the second-highest mark in his career after only his rookie season.
His best games of the season came before Hopkins got injured, proving that at this point he's only a complementary receiver in a pass-first offense, but that's all the Chargers need him to be. There's also the issue that Green plays primarily on the outside, but surely a player of his experience can adapt to what a team needs. He has logged enough snaps in the slot to think so, and as with Kirk, he could rotate with Allen between the slot and outside.
Signing a player like Green could be fruitful for reasons on and off the field, and the commitment could be short as the Chargers try to maximize Herbert's rookie window.