The India Test seamer arrives for three four-day games and five in the 50-over competition, while New Zealand seamer Henry could be available to face Warwickshire next week
Kent have added India seamer Navdeep Saini on a short-term overseas deal for a portion of the remainder of the season.
The 29-year-old has signed up for three LV= Insurance County Championship matches and five in the One-Day Cup, which takes place in August, subject to visa and regulatory approval.
Matt Henry is also set to re-join the club after a stint in 2018 - he took 75 wickets in 11 outings - and is in line to play against champions Warwickshire at Edgbaston starting on Tuesday (July 19).
"It's a great opportunity to play county cricket and I’m looking forward to giving my all for Kent," said Saini.
Director of cricket Paul Downton added: "In a year when it's been difficult to take wickets, we're excited to have the opportunity to add a fast bowler of Navdeep's quality to our squad."
Matt Henry earned cult status at Kent (Clive Rose/Getty Images)
Saini played for India in the four-day first-class warm-up matches against Leicestershire last month but was not involved in the fifth Test against England at Edgbaston.
He has played two Tests, eight one-day internationals and 11 T20Is for India, but is not involved in his country's white-ball plans this summer.
Those outings in the five-day format came memorably in the third and fourth Tests against Australia in 2020/21 when India drew in Sydney and then won memorably in Brisbane after a thrilling fifth-day run-chase.
Jackson Bird's season-ending should injury has forced Kent to get creative with their overseas recruits.
Jacob Duffy signed up on a short-term deal but has since re-joining New Zealand's European tour.