I'd like to define colors for my feature layer categories from a field to ensure that the colors are always consistent, even though I may wipe and re-load data regularly from this feature layer. So, for example, "Animal01" would always be #FFFFFF and that hex value would be stored in my attribute table.
It looks like this is possible in Pro: https://support.esri.com/en-us/knowledge-base/how-to-apply-hex-or-rgb-color-codes-from-an-attribute-f-000024233 - is this possible in AGOL? I'm going to be using a script to truncate and append to this feature layer regularly, so I need a solution that is going to work in AGOL without the go-between of Pro.