My vision -> I would like create page with picture in header, pager in footer and content ofcourse.

My sample code

		await jsreport.documentStore.collection('templates').insert({
			content: '<div style"height: 15mm;background-color: yellow;">Vokurka</div>',
			shortid: 'header',
			name: 'header',
			engine: 'none',
			chrome: {
				width: '15mm',
				height: '15mm'
			},
			recipe: 'chrome-pdf'
		})

		await jsreport.documentStore.collection('templates').insert({
			content: '<div style"height: 20mm;background-color: cyan;">Kedlubna</div>',
			shortid: 'footer',
			name: 'footer',
			engine: 'none',
			chrome: {
				width: '15mm',
				height: '15mm'
			},
			recipe: 'chrome-pdf'
		})

		resp = await jsreport.render({
			template: {
				content: '<p><%= magicWord %> je male zviratko</p>',
				engine: 'ejs',
				recipe: 'chrome-pdf',
				pdfOperations: [
                                                { type: 'merge', renderForEveryPage: true, templateShortid: 'header' },
                                                { type: 'merge', renderForEveryPage: true, templateShortid: 'footer' }
                                               ],
				chrome: {
					//waitForJS: true,
					format: 'A6',
					landscape: true,
					marginTop: '20mm',
				}
			},
			data: {
				magicWord: "Telatko",
			},

		})

• you should not mix page sizes when merging multiple pdfs. So remove the format and chrome width/height.
• don't mix page orientation when merging pdfs. So remove chrome.landscape
• the both header and footer are rendered to the same place. Make sure you position footer to the page bottom
• you are missing chrome marginBottom in the main page

The best is really to open studio and check examples in the docs
https://jsreport.net/learn/pdf-utils
For example this one
https://playground.jsreport.net/w/anon/BkEHf9MNG-5