How to remove Aesir virus?

Some of these ransomware programs have been cracked, most have not. You can use the ID Ransomware online tool to help you determine if your variant has been cracked. If it has then you're one of the lucky ones and should be able to recover most of your files.

https://id-ransomware.malwarehunterteam.com/index.php

Otherwise your only options are to restore from backups or pay the ransom and pray (never a good choice). Removal is generally fairly straightforward but I don't risk it in these circumstances. I'd just reformat and start over.

That tool only claims to be able to remove the malware it doesn't actually claim to be able to decrypt the files. Unfortunately it's unlikely that you can decrypt any of the files you've lost, you may be able to right click on the folders which contain the encrypted files and select restore previous versions. This will let you know if there are any saved versions of the folder which predate the ransonware infection, unfortunately many computers don't have versioning turned on and some ransomware corrupts them as part of its run, so this may not solve the issue. At that point you can recover them from a backup if you have one but there isn't much you can do.

As far as removing the virus, I've found malwarebytes can often remove the infections but honestly you are better off checking to see if you can recover the files, then backing them up and factory restoring the system. This is about the only way to be certain that the infection is gone.

It is still really not possible to decrypt files encrypted by the Locky Ransomware. Do you have a valid backup?

This version of locky, using the .aesir extension, is brand new. As far as I'm aware no ones managed to decrypt even the older versions so it's highly unlikely anyone has managed to get through this version.

As far as I know the above experts are correct? You can't restore, and neither can any software.  I don't see it claiming to decrypt either.  You can check on the No More Ransom project website, Nomoreransom.org., to see if there is a decryptor.