Main platform particularly when games are BCD, keep an eye on the site for updates.
https://www.watchloi.ie/
RTE Player for games being broadcast on TV but a VPN might need to be used in some cases if abroad. Eir Sports also cover some games so subscription needed. Some betting websites have poor quality streams. Some clubs may cover their own games eg preseason but ye'd have to keep an eye on club media for details, or indeed here on Foot.ie where details are likely to be posted.
I know nothing of any other sites or methods to see or stream games games without having a sub or tv licence!!