My wife is Japanese. I’ve instructed my daughters to identify as either asian or mixed if available. they are ornery and will check both white and asian if mixed isn’t on the list. this tends to create certain program issues for things.
Most US ‘asians’ I’ve met tend to be VERY traditional/conservative.
You can write in whatever you like and check whichever boxes you want on the 2020 census form. The data will be reported in the “Two-or more races category.”
From the Census Bureau: “An individuals response to the race question is based upon self-identification. The Census Bureau does not tell individuals which boxes to mark or what heritage to write in. For the first time in Census 2000, individuals were presented with the option to self-identify with more than one race and this continued with the 2010 Census. People who identify with more than one race may choose to provide multiple races in response to the race question. For example, if a respondent identifies as “Asian” and “White,” they may respond to the question on race by checking the appropriate boxes that describe their racial identities and/or writing in these identities on the spaces provided.”