Yet another Russian Republic may have been semi-presidential for a period. In 1993 the Republic of Tuva passed its constitution. It is slightly unclear, but there is at least some basis to call the constitution semi-presidential.
Art. 70 of the constitution stated that the president shall be directly elected for a five-year term.
Art. 69 stated that the president was head of state and of executive power.
Art. 79 stated that the government shall consist of the head of government, ministers etc.
Art. 80 stated that the government must resign if the Supreme Hural (legislature) votes no-confidence in the government. Also, this article stated that the government is accountable to the president.
All of this seems to make Tuva semi-presidential. However, the complicating factor is that, in the translation I have (Raworth, Constitutions of Dependencies and Territories), Art. 73 (3) stated that the president is head of government. So, it is not clear that there was ever a separate position of prime minister. If not, then the system would not have been semi-presidential on the basis of the definition used in this blog.
Wikipedia reports that Sherig-ool Oorzhak was elected as president in 1993 and again in 1997. In 2001 the constitution was amended. The presidency was abolished completely, so that Sherig-ool Oorzhak could remain in power and avoid a term limit.