[anuragsoni]

If the older version is available in the snap repository it is is possible to install it. For example:

snap info go shows:

  name:      go
  summary:   Go programming language compiler, linker, stdlib
  publisher: Michael Hudson-Doyle (mwhudson)
  store-url: https://snapcraft.io/go
  contact:   [e-mail]
  license:   BSD-3-Clause
  description: |
  This snap provides an assembler, compiler, linker, and compiled libraries
  for the Go programming language.
  snap-id: Md1HBASHzP4i0bniScAjXGnOII9cEK6e
  channels:
    latest/stable:    1.16.7           2021-09-08 (8298) 94MB classic
    latest/candidate: ↑                                       
    latest/beta:      ↑                                       
    latest/edge:      devel-8d2a9c32a2 2021-09-17 (8356) 99MB classic
    1.17/stable:      1.17             2021-08-17 (8172) 99MB classic
    1.17/candidate:   ↑                                       
    1.17/beta:        ↑                                       
    1.17/edge:        ↑                                       
    1.16/stable:      1.16.7           2021-09-08 (8298) 94MB classic
    1.16/candidate:   ↑                                       
    1.16/beta:        ↑                                       
    1.16/edge:        ↑                                       
    1.15/stable:      1.15.15          2021-09-08 (8304) 95MB classic

...

To install an older version you can run

  snap install go --channel=1.15/stable --classic

[alyandon]

That's not a generic mechanism at all though - right? It is only possible if the snap publisher has decided to support multiple release channels.