This research aims to classify the various types of Indonesian slang employed by virtual YouTubers in Hololive Indonesia clips. It endeavors to identify the translation techniques used when rendering Indonesian slang terms into English subtitle and evaluate how these techniques affect translation quality in terms of accuracy, acceptability, and readability. The research data were analyzed using a descriptive qualitative method, drawing from both documentary sources and informants. The data comprised Indonesian slang expressions extracted from the dialogues of Hololive Indonesia virtual YouTuber clips. Informants consisted of two raters who validated the data and assessed translation accuracy, along with native English speakers who evaluated acceptability and readability. Data selection followed a purposive sampling technique. Data collection methods included content analysis and focus group discussions.

The study identifies 58 instances of Indonesian slang in Hololive Indonesia virtual YouTuber clips, with code-mixing being the most prevalent (19 instances) and relexicalization being the least frequent (one instance). Notably, the analysis uncovers nineteen instances of code-mixed slang across four derivative types, predominantly involving a fusion of Indonesian with English and Japanese. This linguistic phenomenon appears influenced by characters' cultural and language backgrounds, reflecting the adoption of slang words from English and Japanese.

The results indicate an average accuracy score of 2.94, showcasing highly accurate translations. This score is attributed to techniques like standardization, replacement, and adaptation. These methods enable effective translation of Indonesian slang in English subtitle, albeit with some stylistic trade-offs. In terms of acceptability, the average score of 2.286 reflects positive reception, though the replacement technique, particularly for morphological and profane slang, led to unacceptable translations. For readability, the average score of 2.379 suggests easy comprehension, with standardization enhancing overall readability. In summary, the findings highlight that the use of techniques like standardization, replacement, and adaptation enhances the quality of translating Indonesian slang into English subtitle.