I have the same issue, this is the closest I've got to a solution by using HeaderClass

<PropertyColumn Property="x => x.goods_value" HeaderClass="d-flex justify-end" Title=@Loc["goods"] Sortable="false" Filterable="false" CellStyle="text-align: right" Format="N2"/>

It works for one column, but when I apply the same to another column they just become stacked. I'm no css expert so I'm probably missing something. I've just updated to 7.0.0-rc.1 and I can't see that it behaves any differently.

You can use this solution also:

.header-layout {
display: flex;
justify-content: space-between;
align-items: center;
}

.column-options {
order: -1; /* Forces icons to the left */
}

.column-name {
order: 1; /* Aligns text to the right */
text-align: right;
flex-grow: 1;
}

<PropertyColumn Property="x => x.Quantity" Format="N2" Title="Quantity" HeaderClass="header-layout">

Apply a HeaderClass to the column

<PropertyColumn HeaderClass="custom-header">

Then use the class to modify the<span> element within the header:

.custom-header span {    display: block !important;    text-align: right !important;}