Hey — I love how languages borrow and reshape words, and 'eccentric' is one of those fun little travelers. In Tagalog, the closest direct translation most people use is 'eksentriko' — it's basically the loanword adapted to Tagalog phonetics. If you say, 'Siya ay eksentriko,' it communicates that someone behaves in an odd or nonconformist way. That term is commonly used in writing and casual speech when you want a neutral-to-descriptive label.
If you want something more colloquial or naturally Filipino, I'd say 'kakaiba' or the phrase 'may kakaibang ugali.' Those capture the everyday sense of 'unusual' or 'quirky' without sounding clinical. For example, 'May kakaibang ugali siya' sounds softer and more conversational than calling someone 'eksentriko.' Depending on tone, 'kakaiba' can be affectionate, bemused, or mildly critical.
There are also shades to watch for: words like 'baliw' or 'siraan' are much stronger and imply mental instability or insult, so I avoid them unless the context really demands it. For formal contexts, 'eksentriko' or 'hindi pangkaraniwan' fit nicely; for casual chat, use 'kakaiba' or 'may kakaibang kilos.' Personally, I like calling quirky creators or characters 'eksentriko' in a fond way — it often means they’re interesting, not broken.