Can anyone pls confirm if it is feasible to have sorting along with filtering in a nested gallery and has implemented similar to this in the past. Pls share with us if its possible. It will be a great help.

GroupBy.Let's consider = your data source is MyData with columns ProjectName, ID, and others.
1. Use GroupBy to group items by ProjectName: You can do this at initiation of screen like screen's OnVisible event.
ClearCollect(
colGroupedProjects,
GroupBy(
MyData,
"ProjectName",
"ProjectItems"
)
)
Items property to colGroupedProjects. Then, inside the outer gallery, add a nested gallery whose Items property is ThisItem.ProjectItems to show the grouped records.I am considering you have a toggle control named tglAllProjects:
tglAllProjects is On, show all projects.ddProject - you have project list in the dropdown).You can incorporate filtering before grouping like this:
ClearCollect(
colGroupedProjects,
GroupBy(
If(
tglAllProjects.Value,
MyData,
Filter(MyData, ProjectName = ddProject.Selected.Result)
),
"ProjectName",
"ProjectItems"
)
)
Finally, we can sort the grouped items inside each group by the ID column. In the nested gallery inside the outer gallery, set the Items property to:
Sort(ThisItem.ProjectItems, ID, Ascending)