A custom font can be registered with the engine so it embeds into the exported dashboard — text renders identically anywhere.

Add the font, then export.
var Stimulsoft = require('stimulsoft-dashboards-js');

Stimulsoft.Base.StiFontCollection.addFontFile('./Font/LongCang-Regular.ttf');

var report = Stimulsoft.Report.StiReport.createNewDashboard();
report.loadFile("Dashboard.mrt");

report.exportDocumentAsync(function (pdfData) {
    require('fs').writeFileSync('./Dashboard.pdf', Buffer.from(pdfData));
}, Stimulsoft.Report.StiExportFormat.Pdf);

How it works. The engine resolves and embeds the registered font during export, so custom typography survives into the output file.