I'll add this feature to the next release, but it is interesting to note that this may be implemented in the existing library entirely client-side without requiring any code modification to ScottPlot itself:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();

        formsPlot1.Plot.Add.Signal(Generate.Sin());
        formsPlot1.Plot.Add.Signal(Generate.Cos());

        // use a custom tick formatter to create properly sized placeholder tick labels
        ScottPlot.TickGenerators.NumericAutomatic tickGenY = new();
        formsPlot1.Plot.Axes.Left.TickGenerator = tickGenY;
        tickGenY.LabelFormatter = (x) => "-0.00";
        ScottPlot.TickGenerators.NumericAutomatic tickGenX = new();
        formsPlot1.Plot.Axes.Bottom.TickGenerator = tickGenX;
        tickGenX.LabelFormatter = (x) => "-0.00";

        // create tick modifier labels and add them to the plot
        ScottPlot.Plottables.TickModifierLabel mod1 = new(formsPlot1.Plot.Axes.Left);
        ScottPlot.Plottables.TickModifierLabel mod2 = new(formsPlot1.Plot.Axes.Bottom);
        formsPlot1.Plot.Add.Plottable(mod1);
        formsPlot1.Plot.Add.Plottable(mod2);

        // add extra space on the bottom to make room for the label
        formsPlot1.Plot.Axes.Bottom.MinimumSize = 50;

        // add a pre-render hook to modify tick labels just before each render
        formsPlot1.Plot.RenderManager.RenderStarting += (s, e) =>
        {
            mod1.UpdateTickLabels();
            mod2.UpdateTickLabels();
        };
    }
}

public class TickModifierLabel : IPlottable
{
    public bool IsVisible { get; set; } = true;
    public IAxes Axes { get; set; } = new Axes();
    public IEnumerable<LegendItem> LegendItems => LegendItem.None;
    public AxisLimits GetAxisLimits() => AxisLimits.NoLimits;

    public IAxis Axis { get; }
    public LabelStyle LabelStyle { get; } = new();

    /// <summary>
    /// This logic determines where the text will be placed relative to the data area
    /// </summary>
    public Func<PixelRect, Pixel> GetTextPixel { get; set; }

    private int Exponent = 0;

    public TickModifierLabel(IAxis axis)
    {
        Axis = axis;

        if (axis is AxisPanels.LeftAxis)
        {
            LabelStyle.Alignment = Alignment.LowerLeft;
            GetTextPixel = (PixelRect dataRect) => dataRect.TopLeft;
        }
        else if (axis is AxisPanels.BottomAxis)
        {
            LabelStyle.Alignment = Alignment.UpperRight;
            GetTextPixel = (PixelRect dataRect) => dataRect.BottomRight.WithOffset(0, 20);
        }
        else
        {
            throw new NotImplementedException($"{axis.GetType()} is not yet supported");
        }
    }

    public virtual void UpdateTickLabels()
    {
        var tickPositions = Axis.TickGenerator.Ticks.Select(x => x.Position);
        double tickSpan = tickPositions.Max() - tickPositions.Min();

        Exponent = (int)(Math.Log10(tickSpan));

        double multiplier = Math.Pow(10, Exponent);
        for (int i = 0; i < Axis.TickGenerator.Ticks.Length; i++)
        {
            if (!Axis.TickGenerator.Ticks[i].IsMajor)
                continue;

            double position = Axis.TickGenerator.Ticks[i].Position;
            double divided = position / multiplier;
            string label = $"{divided:0.00}";
            Axis.TickGenerator.Ticks[i] = Tick.Major(position, label);
        }
    }

    public virtual void Render(RenderPack rp)
    {
        Pixel px = GetTextPixel.Invoke(rp.DataRect);
        using SKPaint paint = new();
        rp.CanvasState.DisableClipping();
        LabelStyle.Render(rp.Canvas, px, paint, $"1e{Exponent}");
    }
}

Ticks: support tick labels with multiplier notation #4530

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