I’ve just tested the endpoint and it does return teams with either the name or the country “England”.

see :
“results”:771
"teams":771 items
[100 items
0:{11 items
"team_id":10
"name":“England”
“code”:NULL
"logo":“https://media.api-sports.io/teams/10.png”
“country”:“England”
“founded”:1863
"venue_name":“Wembley Stadium”
“venue_surface”:“grass”
“venue_address”:“Stadium Way, Wembley, Brent”
“venue_city”:“London”
“venue_capacity”:90000
}
1:{11 items
"team_id":33
"name":“Manchester United”
“code”:“MUN”
“logo”:“https://media.api-sports.io/teams/33.png”
“country”:“England”
“founded”:1878
"venue_name":“Old Trafford”
“venue_surface”:“grass”
“venue_address”:“Sir Matt Busby Way”
“venue_city”:“Manchester”
“venue_capacity”:76212
}