My hypothesis: your company can afford paying your team for a few days or weeks before termination of work contract and loss of pay. During that time, developers can use company computers and browse the world wide web.
So, in addition to that answer
Your company has (country and work contract specific) legal obligations. Be aware of them.
Our team is comprised of senior developers who specialize in technology that is no longer used actively by our company.
suggest also your developers to contribute to some existing open source project on github or gitlab
(if possible, even from the current workplace, for a few days), and tell them that this could be positive for future jobs. Also let them read and post on StackOverflow and suggest them to use their real name and provide some contact information (outside of your company).
At least let them install some GNU/Linux distributions (e.g. Debian) on company computers, if they never used Linux. Invite them to read online documentation (e.g. of GNU software).
Perhaps ask each of them to make a talk about some recent open source software they did read about.
For example, if you have a database admin or developer specialized in MySQL, tell him to prepare a 10 minutes technical talk on MongoDB. If your programmer always coded in Java, suggest him to prepare a talk on Scala or Ocaml. If your web developer always coded in PHP, suggest him to prepare a talk on Ocsigen or Haxe. For a C++ programmer, ask him/her a short talk about Rust or Go. If they never heard of Tensorflow, give them a few hours to read about it.
Give a day to prepare the talk, and another day to present and listen to talks to fellow members.
Suggest also each of them to polish their LinkedIn profile.
Let each of them put the talk slides (in PowerPoint, LaTeX, etc...) on the company website or technical blog - or on their own website -, with their name.
A reasonable person would then guess that a layout becomes possible. If they ask a question, answer honestly.
And for a future job, contributing to some existing open source project is a positive thing. Or at least being able to name fancy technologies/languages is valuable.
Also, being able to talk about some fancy technology is an asset for future jobs.
Remember, your teammates are as human as you are.
prepare yourself for the next layoff.
You probably are on the company list also. You should expect to be fired yourself in a few months or weeks.
PS. I selfishly would suggest them to contribute to RefPerSys (still a hobby project of mine), but there are thousands of other open source software projects. I did learn a lot by contributing (in the past) to GCC.
