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This is not a feature of the Prime plotting tools (Native Plot or the Chart Component)..
You can manually generate this effect by creating individual text fields for each annotation and dragging them on top of the plot and adjusting their position accordingly. Unfortunately, if the plot moves or changes, you'll have to re-adjust your lablels.
Using Luc's SNS sheet.
https://community.ptc.com/t5/Mathcad/Toolbox-Text-plotting/m-p/765693