Quick script: Align ĦŁł...

align_composites_with_offsets.py

MacroTab.title = "Align ĦŁł..."
glyphsToAlign = (
	"Hbar",
	"Lslash",
	"lslash",
  # add more glyph names here
	)

Glyphs.clearLog()
Glyphs.showMacroWindow()

font = Glyphs.font
print(font.familyName)
for m in font.masters:
	for glyphName in glyphsToAlign:
		g = font.glyphs[glyphName]
		l = g.layers[m.id]
		if not l.components:
			print(f"⚠️ {m.name}: no components in {glyphName}.")
			continue
		firstComp = l.components[0]
		compWidth = firstComp.componentLayer.width
		leftOffset = int(firstComp.x)
		rightOffset = int(l.width-firstComp.x-compWidth)
		if abs(leftOffset) <= 1:
			leftKey = None
		else:
			leftKey = f"==+{leftOffset}".replace("+-","-")
		if abs(rightOffset) <= 1:
			rightKey = None
		else:
			rightKey = f"==+{rightOffset}".replace("+-","-")
		l.leftMetricsKey = leftKey
		l.rightMetricsKey = rightKey
		for c in l.components:
			c.makeEnableAlignment()
	print(f"👍🏻 {', '.join(glyphsToAlign)} aligned in {m.name}.")

for glyphName in glyphsToAlign:
	g = font.glyphs[glyphName]
	if g.leftMetricsKey and all([not x in g.leftMetricsKey for x in ("+=", "-=")]):
		print(f"🚨 Removing glyph-wide left metrics key ‘{g.leftMetricsKey}’ for {glyphName}.")
		g.leftMetricsKey = None
	if g.rightMetricsKey and all([not x in g.rightMetricsKey for x in ("+=", "-=")]):
		print(f"🚨 Removing glyph-wide right metrics key ‘{g.rightMetricsKey}’ for {glyphName}.")
		g.rightMetricsKey = None

font.newTab("/"+"/".join(glyphsToAlign))
print("✅ Done.")

Glyphs 3.x script for the Macro window.