I have been told that if i have a legitimation card (diplomatic status) and i have a local licence of an asian country, i can endorse my license into a swiss one without a practical test?

if you are india then you are allowed for 1 year from first entry, thereafter, you need to apply for swiss license. best option is to get it converted by just practical test. if you fail - then regular process needs to be followed - theory test and then practical

You have 1 year to exchange it. It must be exchanged also obviously before the date of its expiry. You go to the Verkehrsamt and sign a paper, go to an optician and get a 10 franc eye test and get him to sign the paper and bring it it. Your licence is then transferred into a Swiss one with about 3 weeks. A bit later you'll get a bill for around 110 francs. That's all, had mine done 2 days before it expired back in November.

so you didn't have to pass a test?

No, so long as it was done 1 year of entering the country. But I am from North America, and your country may have a different agreement with Switzerland. Best to check.

There are literally thousands of posts on EF on the subject of obtaining a Swiss driving licence. Yes, your country of origin (of your current licence) does matter, and no, Indian licences can't be exchanged for Swiss licences as US/EU/Australian/NZ etc licences can.

The OP's question (diplomatic status) is unusual. I suggest contacting your local Strassenverkehrsamt or whatever it's called where you live (motor registry).

I would propose to start with questions about conversion from here: [Drivers licence] Conversion and questions