Emily Watson, who is nominated as best supporting actress for "Hamnet", said there had been a "sense of magic" on the set that Zhao had "miraculously" transferred to the screen.
"She did it, I don't know how she did it, but she did it," she told Reuters on the red carpet.
Leading actor is harder to call, with Timothee Chalamet, star of "Marty Supreme", vying with Leonardo DiCaprio and Michael B. Jordan for their respective performances in "One Battle After Another" and "Sinners".
Ian Sandwell, movies editor at Digital Spy, said Chalamet had been picking up awards, including a Golden Globe, for the table-tennis movie "Marty Supreme".
"It would be his first (BAFTA), so it probably will happen," he said.
ROBERT ARAMAYO COULD DELIVER SURPRISE
The BAFTAs could deliver a surprise, however, and reward Robert Aramayo for his acclaimed performance as Tourette syndrome campaigner John Davidson in "I Swear".
Asked what it would mean to him to win, Aramayo said: "I haven't even engaged with that thought to be honest with you, I just feel really, really lucky to be on that list of names."
"Sinners" has scored 13 BAFTA nominations, three fewer than its 16 for the Oscars. Wunmi Mosaku, up for best supporting actress, said the recognition for the film from critics and audiences felt "overwhelming, humbling and just bonkers".
Norwegian film "Sentimental Value" is another strong contender, with eight nods.
Stellan Skarsgard, up for best supporting actor, said the recognition for the low-budget film from both the British and American academies was fantastic.
"It's also a foreign film, but people have learnt to read subtitles, finally," he said.
The 79th British Academy Film Awards will be held in London on Sunday evening, hosted by Scottish actor, TV presenter and director Alan Cumming.
