Tuesday's match at Old Trafford is set to feature the latest chapter in the fiery relationship between Stokes and Samuels.
West Indies batsman Samuels 'saluted' Stokes off the pitch in a Test in Grenada two years ago, a gesture that riled the England all-rounder.
The pair then exchanged words during West Indies' 2016 World Twenty20 final win over England in Kolkata -- a match where Samuels, who made 85 not out, was at the other end when Carlos Brathwaite hit four successive sixes off Stokes in the last over to give the Caribbean side the title.
"I want Ben to be himself," Morgan told reporters at Old Trafford on Monday.
"I want Ben to get into the contest of a game. It's part and parcel of his character and part and parcel of getting the best out of Ben Stokes.
"I've no worries at all."
Following the World Twenty20 final, Samuels said Stokes was a "nervous lad".
But Samuels indicated he would be on his best behaviour in England, having not featured during the recent Test series because of a dispute with West Indies cricket chiefs and a clash with the Caribbean Premier League.
"I'm going to come to England and be a good boy, at least for the start," the 36-year-old Jamaican told the Guardian in an interview earlier this month.
"As long as he (Stokes) keeps quiet, I won't start anything," Samuels added.
Tuesday's match has been given a extra twist by the knowledge Stokes is now just one demerit point away from a ban under the International Cricket Council's code of conduct that could rule him out of two ODIs or one Test, whichever comes sooner.
That has led to suggestions Stokes should get himself banned early during the West Indies one-dayers so he can start England's upcoming Ashes Test series in Australia with a clean slate.
"To be honest, I haven't thought about it," said Morgan. "Maybe I'll speak to Rooty (England Test captain Joe Root) about it."
Morgan added he hoped Stokes could transfer his red-ball bowling form into the ODI arena after the Durham paceman took a Test-best six for 22 in England's series-clinching victory over West Indies at Lord's this month.
"He's almost like having an out and out seam bowler, particularly after bowling like that at Lord's. His confidence is quite high," said Morgan.
Meanwhile West Indies captain Jason Holder played down talk of another Samuels-Stokes flare-up, saying he hoped for a "smooth-sailing series".
"Marlon is one competitive guy," added Holder. "Whatever Marlon needs to do to get fired up, I'm quite happy for him to do, as long as it's in the spirit of the game and doesn't go too overboard."
Tuesday's match will also be England's first ODI since a crushing eight-wicket Champions Trophy semi-final defeat by eventual tournament winners Pakistan in Cardiff in June.
Morgan, reflecting on the lessons learnt from that loss, said: "The most significant thing for us is to get the ball moving off the straight with the seam bowlers during that middle period when the ball gets a bit older.
"Pakistan did it really well and again in the final. It's certainly something we need to improve on."
West Indies require a 5-0 series win -- or 4-0 with a tie or no-result -- over Morgan's men if they are to gain direct entry to the 2019 World Cup in England.
Otherwise the 1975 and 1979 champions face the indignity of a qualifying competition.
But West Indies did enjoy a 21-run Twenty20 victory over England in Durham on Saturday.
"It's not going to be an easy task, but it's not impossible," said Holder. "That win in Durham from the T20 team has given the guys a boost.
"Hopefully we can run on the back of that and bring it into this series."
Ben Stokeschris gayleEngland vs West IndiesEngland vs West Indies 2017eoin morganJason HolderJoe Rootmarlon samuels
First Published: September 19, 2017, 9:40 AM IST