Question malwares behavior

1) Does the behavior of the same malware on different PCs vary a lot? example:

Trojan:Win32/Wacatac.C!ml

PC 1 Trojan:Win32/Wacatac.C!ml, behavior: idle remains

PC2 Trojan:Win32/Wacatac.C!ml, behavior: delete modify files in PC

2) Can a malware like Trojan:Win32/Wacatac.C!ml download other malware, let that perform actions, then delete itself—and would it evade future AV scans? Does it not leave traces to detect in the scan?