How to show these two plots "clearly"?

Question

The following two plots are not visible when shown togather:

  tr1 = With[{a = 0.1}, 
   Composition[TranslationTransform[{0, 0, a}], 
    ScalingTransform[{Sqrt[1 - (2 a - a^2)], 
      Sqrt[1 - (2 a - a^2)], (1 - (2 a - a^2))}]]];
plot1 = Region[TransformedRegion[Sphere[], tr1], 
  PlotTheme -> "Detailed", PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}}, 
  AxesOrigin -> {0, 0, 0}, AxesStyle -> Directive[Black, 17], 
  AxesLabel -> {x, y, z}, AxesEdge -> Automatic]

tr2 = With[{a = 0.2}, 
   Composition[TranslationTransform[{0, 0, a}], 
    ScalingTransform[{Sqrt[1 - (2 a - a^2)], 
      Sqrt[1 - (2 a - a^2)], (1 - (2 a - a^2))}]]];
plot2 = Region[TransformedRegion[Sphere[], tr2], 
  PlotTheme -> "Detailed", PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}}, 
  AxesOrigin -> {0, 0, 0}, AxesStyle -> Directive[Black, 17], 
  AxesLabel -> {x, y, z}, AxesEdge -> Automatic]

Show[plot2, plot1]

How can one plot these with different colors and adjust the transparency such that they are visible neatly?

Answer 1

RegionPlot3D[Evaluate[TransformedRegion[DiscretizeRegion@Sphere[], #] & /@ {tr1, tr2}], 
 PlotTheme -> "Detailed", 
 PlotLegends -> (Defer[TransformedRegion[Sphere[], #]] & /@ {"tr1", "tr2"}), 
 PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}}, 
 AxesOrigin -> {0, 0, 0}, 
 AxesStyle -> Directive[Black, 17], 
 AxesLabel -> {x, y, z}, 
 PlotStyle -> {FaceForm[[email protected], Red], FaceForm[[email protected], Green]}, 
 AxesEdge -> Automatic]