The phrase "are traditionally expected to" is correct and usable in written English.
It can be used when discussing societal norms, customs, or roles that are commonly anticipated in a particular context or culture.
Example: "In many cultures, children are traditionally expected to respect their elders and follow their guidance."
Alternatives: "are commonly anticipated to" or "are usually required to".
Although mid-term elections are traditionally expected to favour opposition parties, Labour is playing down expectations of making significant gains with sources keen to stress the local authority elections are mainly being staged in Conservative heartlands.
"Men in relationships are traditionally expected to be more reserved, less emotional.
Consider the fact that Republicans are traditionally expected to favor business interests more than Democrats.
The good part is that the veteran players who would take your number are traditionally expected to compensate you for your troubles.
Such skills are to be found primarily in Foreign Area Officers, but that is another career field whose practitioners are traditionally expected to commit career suicide.
Perhaps the most telling criticism is that Corbyn is simply not very bright, or certainly not as bright as leaders are traditionally expected to be.
Food banks were traditionally expected to solicit food in only the counties they served.
Widely referred to as "l'hystérique", she is a kind of anti-model of the presidential mistress, who is traditionally expected to be a woman of elegance and discretion.
In this area sisters and brothers were traditionally expected to avoid speaking to one another, and a sister was expected to crouch in her brother's presence and to show respect in other ways.
One of the striking features of the judges' televised discussion in the run-up to the prize announcement was the extent to which they discussed all six of the shortlisted books in emotional terms: essays on cities, works of history and biography were repeatedly praised for moving the reader to laughter or tears - just the kind of response that fiction is traditionally expected to provoke.
Although the role of antioxidants is traditionally expected to be in response to oxidative stress, reactive oxygen species (ROS; e.g., hydrogen peroxide) and ROS-scavenging molecules (e.g., APX) are also involved in transcriptional regulation [47], [48].
